In Silent Hill 2, most levels cannot be exited until completion. This can be very frustrating if one neglects to pick up the discreetly placed music box that is necessary to complete the hotel puzzle before entering the building.
During the second day of investigation in Apollo Justice: Ace Attorney Case 5: Turnabout Substitution, it is possible for the game to not add one piece of important evidence to the Court Record, even though it is supposed to do so. Since that evidence is necessary the following day in the courtroom, when cross-examining Rhea Wits, it makes the game unwinnable.
In Pottermore, during the Chamber of Secrets section, you're supposed to brew some Polyjuice Potion to proceed. To do this, you have to play a potion making minigame, and if you screw up too badly, your cauldron blows up and you've to purchase a new one. Fair enough, except there's a limited amount of money available to collect in the game, so if you blow up too many cauldrons, you may end up unable to proceed.
In Tales of Destiny, it is possible to equip the Sorcerer's Ring (a puzzle solving device) to a character who leaves the party and cannot be regained until a certain amount of in-story progress has been made. If you give the ring to someone like Johnny or Woodrow, it's not too much of an issue, as you can get them back before you'll need it again, but if you give it to Mary, or worse, Leon... Later games averted this by making the Sorcerer's Ring a key item that doesn't need to be equipped.
In a level of Kirby Super Star, there is a room you can enter only by breaking blocks on either side of the door with one of Kirby's powers. Standard issue Kirby is completely unable to move or break these blocks, so if you enter the room, clear out the baddies, but lose whatever powers you used to get in (intentionally or otherwise), you won't be able to get back out. Entering and exiting the room causes the blocks to respawn (but not the enemies), and Kirby can't suck in enemies beyond physical boundaries like walls, so you're forced to hit reset. This is probably the highest level of difficulty you will see in the entire game. It was eventually fixed in the DS remake.
At the end of .hack//G.U. Vol. 3, when you're inside Cubia before fighting the final boss, there is a save point. If you save there and aren't strong enough to beat the Anti-Existences and/or Cubia's Core, then you will of course die; when you die, you reload one of your save files. Thus, if your only save is at that point, you're screwed. The game does recommend that you save on a separate save file since you can't return to town, though.
"Welcome to Rapture", the first level, has an event near the beginning where a splicer kills Johnny and tries to break into your bathysphere. Rarely, the splicer may not kill Johnny, leaving you trapped in the bathysphere.
Arcadia has a plot-critical item in Langford's safe that you need to take to continue the game ( it's the recipe for the Lazarus Vector). However, at that point you can have the Scrounger Tonic, which will let you replace items found in containers with other items. This can cause the plot-critical item to disappear, leaving you trapped in Arcadia.
If you enter Fort Frolic by bathysphere and then immediately leave by the same bathysphere, the curtain that hides Sander Cohen's unfinished 'masterpiece' won't open when you come back. Since you need to have access to what's behind the curtain to progress further in the story, you're stuck here too.
In Fort Frolic, if you use a Hypnotize Big Daddy plasmid to have him kill Silas Cobb in the Record Store before he performs a scripted action summoning his 'cats' to attack you and blowing out the vent that leads out of the store, you'll be trapped in the store basement. That said, you can kill yourself to get teleported to the nearest Vita-Chamber - unless you've turned them off to go for the Brass Balls achievement.
Also in Fort Frolic, unlike the other targets, Martin Finnegan can be shattered while frozen. If this happens, there will be no body to photograph, and you won't be able to complete the aforementioned masterpiece.
Near the end of BioShock 2, if you have Winter Blast 2 or 3, you can freeze and shatter Eleanor, while she's offering you the Summon Eleanor plasmid. If you do, then you can't leave the room because the door won't unlock until you take the plasmid, which you just lost. While it takes an active effort (or at least the unintentional firing of the wrong plasmid) to cause this, it is possible to mistakenly save your game while trying to reload a previous save, leaving your game unwinnable. Also, if you die during a particular boss fight, the Vita-Chamber in which you respawn is on the wrong side of the door that locked you in with the boss.
BioShock Infinite has a glitch near the start of the Finkton level: when you get to the basement of the job center with the motorized patriot and enter the elevator, some players will hold back as they press the button so they can stand in the center. However, when you press the button, the game moves you to the center of the elevator and turns you towards the window, so if you're holding back, you'll back out of it just as the doors close, and will be stuck outside the elevator that you need to take to leave. Time to reload a checkpoint!
Unusually for an educational game, 1997's Where in Time Is Carmen Sandiego? (a.k.a. Carmen Sandiego's Great Chase Through Time) can be made unwinnable. Even though a template game (in which the player chooses which levels they want to play) is Unwinnable by Design, the game tries to make sure that the normal game is winnable. (The ship Yuri Gagarin is in conveniently waits for you and Ivan to take the Chronoskimmer out of the food locker; Carmen never seems to come to pick up the thief the player has to capture...) But they overlooked a bug in the Aztec time period. When you finish assembling the Headdress for Montezuma, you have to put it in your inventory. But if you give it to Ann Tiquity to ask what she says about it, then she'll say, "We must get this headdress back to Montezuma, before he blows his top!" and the headdress will be placed back in the inventory... where it will accidentally spawn another headdress. Now, you can still complete the level (and therefore the game) by leaving the duplicate headdress there. But if you haven't yet gotten the Carmen note (required to beat each level), then you'll have to take the duplicate headdress and put it in your inventory so you can get the note. You then walk into the throne room and are forced to give the headdress to Montezuma (he does not allow you to leave the throne room with a headdress in your inventory). But, because you accidentally duplicated the headdress, you're still stuck in the room because Ann Tikwittee won't let you leave either; each time, she'll say, "We must get this headdress back to Montezuma before he blows his top!" It's unknown if it's fixed in any later versions.
The Game Boy Advance remake of the original Broken Sword had a couple of these because of Game Breaking Bugs. If you go to Spain before going to Syria, then it often causes a glitch which prevents you from going to Syria at all. Also, there is a part early on where you have to make a plaster cast; a glitch lets you do that without having picked up the plaster, which you need to get a key later in the game.
The random nature of the Item World maps in the Disgaea series can potentially produce maps that are unwinnable if you're lacking units capable of reaching the exit or the enemies on the map.
Daggerfall shipped with a number of bugs and glitches that made it impossible to complete the main quest. The plot-breaking bugs were eventually corrected with patches; but one potentially game-breaking bug with the collision detection, which could leave the character stuck in "the void" after falling through a flight of stairs, was never satisfactorily fixed and even pops up in certain parts of Morrowind.
A major problem with Daggerfall is that quests are timed with penalty of failure. This includes the main quests! The most obvious example: when Queen Mother Mynisera tells you to track down a courier who has a letter, you have to wait in a city and meet the courier on a certain date. But the date as stated is wrong! And if you miss the courier, then you cannot redo the quest.
Unlike its predecessor, Morrowind attempts to avert this by telling you outright that "the threads of prophecy have been severed" whenever a plot-essential character dies. However, there are a few essential characters that do not trigger this message, and these are the most aggravating because they are characters that you wouldn't suspect for a minute to be essential to beating the game.
God help you if you store Keening or Sunder in a container and come back later to find that it is gone. There are many ways to beat Morrowind, but you do need these two items at the very least to beat the final boss. Losing either of them, even by accident, renders the game unwinnable.
A number of sidequests can be broken by accidentally selling the related item before realizing that it's required for said quest. Good luck trying to remember which vendor you sold it to 20 hours afterward!
In The Elder Scrolls IV: Oblivion, it is very possible to make the last mission of the Shivering Isles main quest unwinnable. It involves a final battle outside, and if the player character happens to be a vampire that has gone without feeding for a few days, and if it is day outside, and if the player doesn't have enough healing items, the character can die shortly after the final boss is defeated and makes a speech to the player. If you don't save before you leave Sheogorath's throne room, have fun and don't talk to real people for a few hours, as the autosave happens immediately once you're outside. Of course, this can apply to many areas in Oblivion and "Shivering Isles" when one is a vampire.
At the end of the quest "The Break of Dawn", the player is suspended in mid-air above a mountain while talking to Meridia. She's supposed to let the player drift gently back down to earth afterwards, but a glitch can kick in where the player simply gets dropped and suffers fatal fall damage. The game autosaves right before their conversation, so you can get stuck playing through their dialogue and then dying over and over. The only way out is to reload an earlier save and make sure you aren't carrying too much gear.
Certain quests can be broken if they're done in different orders, due to the radiant quest system. One of the Dark Brotherhood Contracts can render Narfi's quest unwinnable due to now making him utterly terrified of you (making it impossible to turn in his personal quest). They can also be broken if they're dependent on a random location and require a certain amount of kills; one of the Dawnguard recruitment quests requires you to go to a random cave and kill a Bear. Unfortunately, it can select a cave where you've long since cleared out the enemies, resulting in no bears spawning in the cave and locking out the entire quest chain.
The NTSC version for the NES is just plain impossible when playing with two players simultaneously — there's a bug in Level 11 in which Player 2's Clinger Winger never starts moving, and so the Hypno Orb runs him over every time. Since the level restarts if either player dies, this will repeat until either player runs out of lives, at which point they need to finish the level on their own if they wish to beat it. Thankfully, it was fixed in the PAL version of the game, as well as in the Sega Genesis port.
In level 9, Terra Tubes, in the NES version, normally you would pass the first section of the level by destroying the gray, self-destructing robots before moving onto the spinning cog section. However, if you don't destroy the robots but rather bypass them by hitting them once and walking by while they're stunned, a glitch can occur where the spinning cog fails to properly render after passing the checkpoint (only half the cog actually appears onscreen). Said cog will not move or kill you, and should you go right and fall down the tube towards the first gate, it's impossible to die or progress further, meaning a reset is necessary.
In The Berenstain Bears' Camping Adventure (or at least certain copies of it), if you played the game in two player mode, the game was completely impossible to win: The vine-springs used to catapult yourself up to higher platforms in Goin' Fishin' would not appear, making it impossible to progress through the level. You could choose to play the first four levels in any order, but had to complete them all to unlock the fifth, making it impossible to access the Haunted Forest with two players through any legitimate means, and therefore impossible to actually win the game unless you played it solo. And if you and your friend decided to play Goin' Fishin' first, you were in for a bad time...
Many of the games in the old Action 52 compilation (for the NES and Genesis/Mega Drive) are unwinnable because of shoddy programming.
Two of them, Alfredo and Jigsaw, are also unplayable (except on a very few emulators).
To give you an idea of just how bad the situation with Action 52 is, the game's developers decided to include a small contest in the game. They put a secret, personalized code at the end of one of the games, Ooze, which (along with taking a photo of the game screen to show that the player did beat the game) would have made players eligible for a grand prize of $104,000. Unfortunately, there were two versions of the Action 52 cartridge. In the better-known version, "Ooze" inevitably hangs two or three levels in, making the game impossible to complete.
In Star Evil, the boss sometimes fails to show up; and if you beat the third boss if it happens to show up, then the last level is a Gray Screen of Death.
Some games, such as They Came, crash when you die or complete a level (again, in the better-known version of the cartridge).
Fuzz Power has an insurmountable rock wall in Level 3.
Active Enterprises was trying to make the Cheetahmen into a Cash Cow Franchise. They started on a sequel to the Action 52 Cheetahmen game, Cheetahmen II. They folded before they could release it, but 1,500 prototype copies were discovered in a warehouse and distributed as bootlegs. It's obvious that the game wasn't finished; in addition to the many annoying bugs and glitches and crippled controls, there is a game-stopping bug where the next level fails to load after you defeat the ApeMan in level 4. You can skip to levels 5 and 6 with a Game Genie, a hacked ROM, or a certain good bad bug; but after you beat the final boss there, the game just stays on the boss screen, no ending cinematic, no credits, nada.
Ninja Assault is another game with No Ending. After you play through the glitched-up fourth stage and defeat the glitched-up boss, the game just stops. There's a cave entrance on the boss screen, signifying that there should be more levels, but they didn't bother to program them.
In the 5th level of Atmos Quake, your ship randomly explodes for no reason, probably due to the glitchy collision detection, making the level unbeatable.
Pikmin has potential to become unwinnable. Libra is placed high atop a large cliff side in the Forest Naval. You can get it down without problems most of the time, but there is a small chance that your pikmin will misstep on their way back down, taking it and them to the abyss below. Libra won't respawn in its old spot, and you can't win the game if you save this: you need all the vital parts at least to win, let alone all the ship parts, and Libra happens to be vital.
Crash Team Racing has a slight bug with the way carts are reset after they fall off of the track. The game has a set distance that is recovered to place the player's carts, regardless of what section of the track is (or isn't) there at the time. This can be especially bad on some tracks that require a long boosting sequence to clear. Fall short, and enjoy the endless loop of the game resetting your cart in the middle of empty space, or a standing start on a single acceleration panel launching you only halfway ad infinitum.
The NES game Heroes of the Lance was especially craptacular for one reason: If the easy-to-die cleric Goldmoon ever dies and you don't retrieve her Blue Crystal Staff, then the game is unwinnable. It doesn't help that she's the default character and so, for beginning players, the most likely to die first.
In the original Phantasy Star I, the game can easily become unwinnable near the end; if the player has the bad idea to save in this particular situation, then they will eventually want to destroy the cartridge. Upon landing in the air castle, the player must fight a particularly tough boss after a long and confusing dungeon. Afterwards, there are three ways to leave the Air Castle: the heroine's teleportation spell, a teleportation item, or a magic nut to turn your cat ally into a flying creature. But it is likely that the heroine will have ran out of MP casting her strongest spells against the boss, that the cat will have bit the dust halfway through the dungeon (rendering him unable to use the magic nut), and that the player will have forgotten to bring a teleportation item. Ten bloody hours down the drain.
In Phantasy Star Universe, there was a glitch in the MAG event mission at the very end. Each player has to take the warp individually to the final block and then stand at a gate which will only open when everyone is accounted for, letting everyone in to spawn the monsters and smash things up until you kill the final one. The glitch? At times, the monsters would spawn before the gate was opened. It's mostly harmless if you ignore them and take their attacks while waiting for everyone to get to the gate; but if someone kills the monsters with ranged attacks, then the monsters will stop spawning around the third wave or so, making it impossible to finish the mission.
You must break into the local museum to steal some items. The regular way of doing this involves using the Red Key Card on the back door to get to the sewers, from where you can access the room with the museum's alarm switch. Turning it on will evacuate the museum, after which you'll be able to enter it — still from the sewers — and take everything you need there, with the automatic robot guards as your only obstacle. However, if you're skilled enough, you can skip all this and just go through the front door, steal the items in broad daylight and escape before getting arrested. Performing such a robbery before obtaining the aforementioned Red Key Card will cause the game to assume you already have that item, which means you can no longer get it for real. Since the Card is needed to open a few more doors later on, you can't complete the game without it.
LBA has a peculiar save system more typical for a console platformer: it keeps the data in a single file which is constantly updated to reflect the stats changes, and also updated whenever you enter a different location. Unless you make use of the "copy saved game" feature, this can get your save file screwed up if you were to, for example, drop into a scene from significant height while having only one HP (which you lose due to hitting the floor) and no extra lives.
Monty Pythons The Meaning Of Life: The PC Game is a point-and-click adventure through the movie and television show as you search for the eponymous philosophical question. Unfortunately, the game has more than one occasion where you can wind up in an unwinnable situation by doing exactly what the game has had you doing the entire time — exploring and clicking on interesting looking junk. It's nearly impossible to reach the last screen because of a fatal glitch that causes a disc swapping menu to fail to appear. As obnoxious as this is, it's almost fitting that something like this would show up in a Monty Python game. The disc swap bug CAN be worked around, but you have to know at what screen it appears to get around it, which you won't know if you aren't looking at a walkthrough.
"Pharaoh", the first secret level of TNT: Evilution (one of the Expansion Packs that came with Final Doom), was rendered impossible to finish because a vital key was erroneously flagged to appear only in multiplayer. The creators of the pack, TeamTNT, quickly released a patch allowing the key to appear in any mode, which also fixed a node-building error that prevented some enemies from appearing. The fixed version was also included in the official id Anthology, but it wouldn't be until the GOG.com release of the game, almost 20 years later, that this version would be sold by Doom creators id Software in widely-available form. Not that it stopped people from discovering how to complete the level without the key in the meantime, of course.
The -nomonsters parameter, which removes all monsters from a level, quite obviously makes it impossible to finish a level that requires a specific monster to die before the exit will open, such as any of the boss levels in the originalnote Strangely, monster spawners and John Romero's head-on-a-pike from the final level in Doom II are unaffected, so a run of that game, skipping the second secret level, would actually be completable.
E2M4: In version 1.1, approaching the yellow key, retreating to a different room, and returning causes the crushing ceiling to be permanently lowered and sometimes blocking access to the key. That version forgot the original ceiling height whenever the crusher stopped.
In the map "Dead Simple" from Doom II, the central staircase raises once you kill all Arachnotrons. If played on Nightmare, Arachnotrons can respawn and be killed off again, allowing you to raise the central stairs out of reach.
"Even Simpler" from Doom 64 is basically a remake of "Dead Simple," only with Pain Elementals thrown in. You have to kill every enemy, including the Lost Souls they shoot out, to advance. If they're killed next to some walls, however, the Souls they are supposed to shoot out get sucked into the walls, making it impossible to kill them.
In Doom 3 a number of doors are supposed to lock behind you once you walk through them. However, it's possible to walk through one of these doors and then back out before they close (usually because an enemy jumped out at you), and end up on the wrong side of the door when it locks, causing you to be unable to proceed furthur.
Another interesting example: You can opt to obtain Sonic's optional upgrade in the Last Story and then save and quit. When you load the game, you'll get text indicating what has last happened in the game, just like in any other character's story. When you obtained the Crystal Ring determines what the text says. (For those who haven't played the game, that's not supposed to happen in the Last Story.) When the "previously" text is finished scrolling, the game will freeze. Interestingly, the background art is the CG of Perfect Chaos as he looked before his final in-game design.
In Sonic Adventure 2 for the Sega Dreamcast, some discs had an error which made you fall through the floor. At the beginning of the last level, meaning there's no way to stop it.
In Sonic the Hedgehog 2, in Wing Fortress Zone, there is one point where Super Sonic can jump off a rising platform when at its peak and barely reach the next level up, which looks like a shortcut, except there are walls on all sides, and the way you came was a floor that can only be passed through from the bottom. The only way to continue is to run out the timer. (There's other places like this, accessible mostly via glitch.)
There's also the infamous "Stupid Pit" in Mystic Cave Zone. It has spikes at the bottom, and is far too deep to jump out of. Get all seven Emeralds, turn Super, fall in, and you now must wait for your rings to run out. An otherwise functionally identical-to-the-original mobile port of the game replaces this spike-filled pit with a spikeless pit that leads to a redone version of the infamous Dummied OutHidden Palace Zone if you fall in.
During either act of Marble Garden Zone, while playing Sonic with Tails following, it's possible to glitch Tails off the screen so you go through the rest of the Zone solo. Doing so prevents Tails from returning to aid you in fighting the Zone's main boss; you're stuck off the screen and out of reach until you reset the game.
Also, you'd better not be Super Sonic when you reach that main boss, or Tails will not appear either. A similar thing happens if you replay that level, play as Super Tails, and hit Eggman more than 8 times before he takes the battle into the skies. However, this was fixed in at least one later rerelease. (specifically, Sonic Classic Collection for the Nintendo DS)
Better not screw around playing Tails with the second controller in Hidden Palace, or he may not automatically get into place to fall to the bottom of the level, making it impossible to proceed.
In Carnival Night Zone, Sonic can get stuck in a quarter pipe's wall if the player makes him go too fast, and it's impossible to get Sonic out. The dev team evidently knew about this but didn't have time to fix it: the American manual Hand Waves it by saying that they are traps that Robotnik lays to take advantage of Sonic's speed.
In Launch Base Zone, if you spindash into a ramp, Sonic will glitch through it and get stuck in it until he dies from the time running out.
Sonic Megamix, a hack of Sonic 1 ported to the Sega CD with enhanced graphics and new level design, has a glitch in version 4.0b right at the end of Starry Night Zone Act 2 that can get you stuck in the wall. It's rather consistent if you're moving quickly, and it's a glaring problem in an otherwise wonderful hack.
In the Hero mission of The Doom, sometimes the Heal Units necessary to save the kidnapped researchers can glitch out and get stuck in midair, making them impossible to use.
There's another one in the fight against Sonic and Diablon. The gimmick of this fight is to bounce off of Sonic in order to reach and attack Diablon. However, if he falls off the arena (say, if he went to attack Shadow near the edge and missed), he doesn't respawn, and Diablon cannot be hit.
In A Wonderful Life, ordering new machinery can render the game unplayable if the machinery arrives on the first day after a chapter change. The only way around this is to avoid ordering machinery in the last season of a chapter, since the exact date the machinery arrives is random.
Similarly, in the North American Harvest Moon DS, two glitches caused both the Witch Princess and the Harvest Goddess, and only them, to be ineligible for marriage. You couldn't get the Witch Princess because the game didn't keep track of dead animals; you couldn't get the Harvest Goddess because Buckwheat Flour was on her lists but not in the game itself. Fortunately, you could still finish the game by marrying another girl. The glitches were corrected in an updated version (DS 1.1) and Harvest Moon: DS Cute. Not that you could marry them in the western translations of the latter..
A similar glitch happens in "Another Wonderful Life." If you woo all three of the bachelors to full hearts and experience all their heart events, then there is a random chance that you will be instantly locked with Rock. Then Rock will be the only one who will propose to you or accept the Blue Feather; Gustafa and Marlin will reject your proposal as if you still lack something, even though your hearts are all accounted for and you witnessed all their heart events. It tends to happen more if you witness Rock's heart event last, but it is not a guarantee.
Saving in a cave while poisoned and sealed can render your game unwinnable if you have low enough HP and no cures for the Standard Status Effects.
There's also the issue of entering a cave accessible only during the winter and being in it when the new year starts. At least in this one, the game politelylocks up.
I Have No Mouth and I Must Scream was edited in Germany to remove Nimdok and his scenario because the scenario was set in a concentration camp. This made it impossible to complete the game — all five characters' scenarios must be finished to reach the last segment.
Sphinx and the Cursed Mummy has a save point in the Castle of Uruk during one of the Mummy's missions. Normally, you will approach the area and see a cut scene between the Big Bad and The Dragon; and then a door would open. However, if you save at the save point, quit, and reload the game, then the door would be closed when you re-start, leaving you trapped there forever. Nasty.
The original MechWarrior for the PC required you to head to a specific planet to begin the sequence to beat the game. But after a certain point in time, going to the planet results in an unceremonious 'Game Over' screen. Typically, by the time you're able to build up your forces to a respectable level, it's too late.
X-COM: Terror From the Deep has the Tasoth Commander. Researching one of these makes researching the Cool Starship for the final assault impossiblenote The reason is that Tasoths are actually not supposed to have commander units, so when they appear anyway, they make the game act strangely. The only species that are supposed to have commanders are Gill Men and Lobstermen. Thankfully, patches keep Tasoth Commanders from showing up for research.
In UFO Aftershock, it's very easy to render the game unwinnable by simply failing to complete the mission where the Starghosts first appear (either by losing the tactical mission or letting the mission time out in the strategic mode). This mission gives you a research topic which is absolutely crucial for finishing the game and if you miss it, you won't get a second chance.
In Inindo for the SNES, you eventually reach a point where you must complete a Fetch Quest to be rewarded with the key to unlock the door to the rest of the game. When you complete the quest and talk to the person with the key, you are asked if you have space in your inventory to accept it and given a yes/no option. If the first character in your party does not have any free spaces in their inventory when you say yes, then the key disappears. There is no way to get another one. If you save the game before realizing that — say, you checked your inventory beforehand and saw that the second character had space in their inventory and assumed that was okay — then the game is now stuck in an unwinnable state.
There's a nonstandard game over in which, if you level accusations at the Big Bad without the evidence on your person or the person of one of your party members, then you will get called on it and hit with a flamestrike spell, against which there is no save and which instantly kills you. Since the invitation's icon looks like any of a dozen scrolls you might be carrying around at the time, and since non-magical game items decay after a certain amount of time...
In the initial release of Baldur's Gate, before the first patch came out, it was possible, though very, very rare for Gorion to kill the Armored Figure during the cutscene at the beginning of the game. This caused the game to lock-up and crash. Since there is no plot immortality flag in BG 1, they instead raised the armored figure's HP to 9999 to keep him from getting killed.
If you start as a wizard in either Baldur's Gate or Shadows of Amn and have only 3 Constitution, then you can't win. You will die in the first in-game cutscenes because enough points of unavoidable damage are dealt to you that your pathetically low Hit Points will be gone. In game terms, this makes sense — in the tabletop Dungeons & Dragons, if any character with a Constitution of 3 ventures out beyond a hermetically sealed clean room, then they're probably not gonna make it.
Using Otiluke's Resilient Sphere on NPCs (to prevent them from getting killed in battle) can sometimes break quests because their triggers can't fire properly.
There is a point at which you have to fight Irenicus (and a bunch of minions) in Spellhold. Normally, you just have to get him down to a certain amount of hit points, triggering a dialogue in which he teleports away. You can then exit Spellhold and continue the game. However, if you somehow get extraordinarily (un)lucky and Irenicus fails his save against Disintegrate, then he does indeed Disintegrate - which renders the game Unwinnable, since he's no longer around to trigger the dialogue and you can't move on. Of course, by all in-universe logic, you'll have won right then because the rest of the game is about chasing and stopping him.
One of the designers of the game, Dave Gaider, made a mod for the Throne of Bhaal expansion pack, making the last battle of the series far more difficult. One of the features is that one of your old enemies, the vampire Bodhi, is teleported in from the Abyss to fight on behalf of the Big Bad. The only problem is that, by then, any clerics you may have in your party are so hugely overpowered that, if you enter the last battle with "turn undead" on, she explodes into chunky giblets before she even has a chance to say her menacing dialogue, stopping the game in its tracks.
Another way the game can become unwinnable is if you accidentally hit a plot-crucial NPC.
In the PC mystery game Sherlock Holmes: Secret of the Silver Earring, the action takes place over the course of a few days. The game is rendered unwinnable on the first day if Holmes neglects to pick up a particular clue. This seems to be a glitch, rather than by design, since failure to pick up any other clues will cause the game to prevent him from moving forward. But the game will allow him to go ahead even if he doesn't pick up the autographed picture in the young woman's dressing room. The player will be unaware that there's a problem until the fourth day in-game, when he is supposed to show that clue to someone; his inability to do so brings the game to a screeching halt.
In the American release of Tokyo Xtreme Racer 3, to face the last opponent and be able to finish the game, you must defeat the other 599 opponents. But one particular opponent, Whirlwind Fanfare, only appears when you have 100,000,000 CP; the maximum CP you can carry is 99,999,990. This glitch makes it impossible to beat the game without using a cheat device. All CP needed / earned was divided by 100 for the US release (to reflect dollars rather than yen), but Whirlwind Fanfare wasn't adjusted.
True Crime: New York City has a laundry list of randomly occurring Game Breaking Bugs that can cause certain missions or the game to become unwinnable, making Save Scumming a necessity. Even worse, the Xbox version has a big bug late in the game that rendered it completely unwinnable due to no fault of the player.
True Crime: Streets of L.A. has a particularly bad (though rare) bug that can make the game unwinnable. Given that the game is a GTA-type, driving cars is natural. So is blowing them up. Ramming a car enough times will make it blow up. Simple enough? But certain in-game cutscenes do not make your car invincible, and the idiot drivers on the road do not stop when your car does. If your car has just enough damage and another car smashes into it during a cutscene, making it explode, then the game will continue after the cutscene on the assumption that you are dead. Add that the game saves after most cutscenes...
In the expansion pack Heart of Winter, there is a scene in which a fight breaks out among members of the tribe the player has been assisting, with the expectation that the player will pile in on the side of the rebels. During this scene, if a friendly tribe member is inadvertently hit (which can easily happen with the mess of area effect spells available to the party by then), all other friendly tribe members will immediately turn hostile. The game will give no indication that this has happened. If this is not noticed and an earlier saved game isn't reloaded, then it is possible to slaughter the entire tribe without realising something is amiss until the NPC who is supposed to trigger the next sequence of events instead attacks and mercilessly butchers the party. If this situation occurs and an earlier savegame is not present, then the game is unwinnable.
Freeing the salamanders' slaves before finding and clicking the broken rope bridge to the ice giants' cave means that the only slave capable of teaching you to repair it is gone. You are now unable to get the sixth sigil required to meet the final boss.
Although extremely difficult, it is technically possible to make Monster Rancher 2Unwinnable. You get a Game Over if, at the start of the month, you have less than 100 G and are unable to feed your monster. The only way to get this situation is if you saved after the last tournament of the month your monster could possibly enter, you have no items to sell, your monster is too young to sell, all of your monsters in storage are too young to sell, and your monster never brings you any item you could possibly sell for money out of the blue. Whew!
In Monster Rancher 3, a minor plot battle in the jungle region of Kalaragi turns into a story-stopper if you lose. Your rival, Gadamon, will (if you lose) demand that you bring her a Dodorin Fruit when next you go exploring. Fair enough, especially when another character tells you where to find them - except that when you search the spot, the game recycles the dialogue from the end of the conversation telling you how to get it, and you get nothing. Not only can you not progress in the subplot, but this brings the entire story to a halt - no other events are available. If you win, however, you progress as usual through the story. Your reward for the subplot's completion? A Dodorin Fruit.
The Addams Family for Game Boy. The only two levels you cannot leave by the same way you came in require items from other levels to reach their exits. When you enter The Toybox, you had better have completed the Boiler Room level to have the Hot Coal weapon; the boss in this level is immune to all other weapons from most directions. At The River, if you didn't bring the fish potion with you, your game is over even if you know the hidden route to walk from one end of the level to the other; the boss is unbeatable without that potion.
In the level 5 basement, it is possible to duck and go through a wall which leaves Pugsley stuck inside the wall with no way out. If this happens reset the game and be careful not to get stuck again.
Two optional levels require you to have completed The River. In The Swamp, you need the Icecube item to float across the swamp sections. In Ice box, you need the icecubes to float across the freezing pools of water or the fish potion to swim across.
The first and second games in the Shadow Of The Beast series. In addition to having exactly one life, a short (first game) or quick-draining (second game) life bar, and no way to save or continue, you can easily make the game unwinnable by screwing up puzzles and failing to collect necessary items before passing the Point of No Return. The third game tones down the Nintendo Hard elements of the previous games, giving the player three lives and making the action scenes much easier with emphasis on puzzles. While it is still easy to screw up the situation beyond repair, it is possible to return to the previous checkpoint by pressing the Help button on the keyboard of your Amiga.
As with all over day-to-day games, Shadow Of The Comet can be rendered unwinnable if you fail to meet a certain person on a certain hour of the day, or fail to get an item at the right time. There's little hint of this.
The first run of Cardfighters DS was literally unwinnable thanks to a game-stopping bug that causes it to crash when a player fights a certain character. None of the NPC battlers can be skipped. Thankfully for those who want this game, they fixed this with a second print.
In the "Operation Rapunzel" level of Medal of Honor: Frontline, if you happen to backtrack for health items or ammo after rescuing the hostage, he may disappear, rendering the level unwinnable.
In one level of Return to Castle Wolfenstein, you have to avoid setting off any alarms and sneak into a truck at the end without being noticed. This level contains a major game-stopping bug, at least in the Xbox version: if you shoot out the last alarm with anything other than the silenced sniper rifle, then the truck driver will still be alerted to your presence, albeit unable to sound the alarm; you won't get a "Mission Failed", but the level will become unfinishable. They should have made alerting the truck driver itself a Non Standard Game Over. Better keep multiple saves; it's a pain to have to play through this level all over again.
There is one part of the game where a scientist gives you an airplane to use for a fetch quest so he can build a rocket to send you to the end of the game. It is possible, through an obscure glitch, to land back in the scientist's lab without the plane. If the player hasn't completed the fetch quest, then the game is now unwinnable (and it is possible to save, ruining the player's progress about 3/4 of the way through an SNES RPG).
It's also possible to get stuck in the third part of the game, the medieval land, after defeating the Chess monster and going through a cavern and ending up in the desolate town. You climb a massive bunch of ramps, and at the top you are brought back to the populated town, where you are expected to fight a boss in the castle. Go through the cave again, and you're stuck in the desolate town because your airride won't come back.
One dungeon is filled with collapsible bridges. This is standard fare for video games; but unlike the standard Magical Self-Repair Bridge, once these collapse, they're gone forever. This leads to unwinnable situations—if you use an item or formula to escape before defeating the dungeon's mini-boss but after crossing the bridge to get to the dungeon, you'll be unable to return and thus unable to complete the dungeon. If you're unfortunate enough to save while you're outside, then your save file is rendered unwinnable.
The area before the Verminator is inescapable and inhabited by nothing but fast-moving rats that are worth a piddly 4 EXP each. If you're underleveled and you saved, then the game is as good as unwinnable. Did we mention that the Verminator is That One Boss and that this area is 3/4 of the way through the game? Ironically, this boss can be avoided altogether by utilizing a glitch in the previous area; but if you ever go into his room, then the game will lock the door and not open it until the code signifying you've beaten the boss goes through. Since the boss doesn't appear after you've used that glitch, it will be impossible to initiate this code, and the player will be forced to reset. Unwinnable revenge!
Like the aforementioned 7800 port of Impossible Mission, the disastrous DOS port of the original Teenage Mutant Ninja Turtles is unwinnable due to no fault of the player, since there is a jump in the sewers of Area 3 that is impossible to negotiate due to a low ceiling. Unless, that is, you use a cheat code to walk through walls or skip levels, or take advantage of a particular glitch.note There is a very strange glitch that can be used to bypass this (perhaps it was used by the developers to speed testing). If you walk to a certain point on the overworld map, your Turtle will swing the rope and begin climbing on the map. If you then enter a certain building, you can fall through a level and end up in a later part of the game.
Likewise, the Commodore 64 port of Rastan has an impassible jump in the ice level.
In Tiny Toon Adventures: Buster Busts Loose, there's a part near the end of the second level where the game takes control away from you so that Buster can show off and stand as close as possible to the edge of the roof of a train wagon (which is next to a bottomless pit, naturally) during a Auto-Scrolling Level before he dashes off and uses a convenient ramp to make it to the final part of the stage right before the screen is about to push him off the train. The problem is that the game defaults to R button being set as "dash", and if you've changed it to something else, Buster will just stand there and get killed repeatedly since you can't change controller settings in the middle of the game.
The Game Boy Advance version of The Lord of the Rings: The Fellowship of the Ring has a bug that makes the game unwinnable if you do not save at a specific point during a transition between scenes. Compounding the problem, saving just an instant too early means you're stuck in a sequence of "Load game - automatically trigger scene transition - game freezes - turn off game".
The C64 game Space Rogue was, for all intents and purposes, virtually Unwinnable because the required Plot Coupon item needed to rig your ship to go to the ant invader's home sector cannot be obtained. It is supposed to be a randomly drawn item from Robocrook's chance game (making it a pure luck scenario), but it never drops.
In the PC version, this was fixed, but there's not much in the form of in-game help, and there was no GameFAQs to look this stuff up on back then. After the third or fourth random piece of junk, most people stopped checking with Robocrook and didn't know they had to.
In the Game Boy game The Bugs Bunny Crazy Castle 2, the hammer at the beginning of stage 16 is not needed. But if you miss a key early in the level, you'll need the hammer to get back to it; otherwise, you'll have to find an enemy and kill yourself. But as it's also one of the few stages where you can kill every enemy, it's possible to wind up in an enemy-free stage, with no way to beat the level, and no way to kill yourself to try again.
In Portal it is possible, if you try very hard, to accidentally lose a weighted storage cube to a portal glitch that makes it randomly disappear; this makes most levels unwinnable.
In the instances of making the levels unwinnable that the developers have figured out, GLaDOS (your instructor for the game) will practically call the player an idiot, stating that it is no fault of the Enrichment Center that you have managed to trap yourself.
A much easier way to screw up your game completely is to fall into toxic waste and simultaneously hit one of the badly placed autosaves.
It is much easier to make the game unwinnable when playing the bonus maps (the harder versions of Rooms 13-18) by, say, dropping a weighted cube in the goo where it cannot be recovered. This is also played with in one of the rooms: you have to drop the Companion Ball into the incinerator before the timer goes off. This involves moving a lot while a timer is running. If you deliberately make the level unwinnable, GlaDOS will open an "emergency escape hatch," which means that you have to move about a tenth as far to get the ball into the incinerator.
Grand Theft Auto: San Andreas has a well-known glitch occurring in the later mission Madd Dogg. You're supposed to line up a truck full of hay under down-and-out rapper Madd Dogg before he jumps to his death, but for still-unconfirmed reasons he can commit suicide as soon as the mission cutscene ends. Fans speculate that this is caused by too many cheats being saved, though this has been mostly discredited. Another theory is that the pedestrian riot cheat has been activated, which makes Madd Dogg walk off the roof to attack the nearest person. There is no way to complete the story mode on the same save file if this happens.
The worst Game-Breaking Bug in all of the series has to be the Purple Nines glitch in Grand Theft Auto III. If you complete the D-Ice mission Rumble, it clears the existence of an entire gang. The problem occurs that once you save, the bug affects all saves so the game will never load any more Purple Nines. That makes D-Ice's first mission impossible on any future game saves, as it entails gunning down a set amount of the now non-existent Nines.
Grand Theft Auto IV's last mission features a jump from a bike to a helicopter. You then hang on the chopper and have to press a certain button to climb into the cockpit. Some copies are affected of being unable to get into the chopper, regardless how often you press, making this an Anti-climax.
PC-gamers have the option of changing the button in the options. Console users are still screwed; no one from Rockstar Games knows what the bug is or where it came from.
A semi-rare bug in Grand Theft Auto IV: The Lost and Damned can lead the game to not give you any more missions after the museum mission is finished, meaning the game story can't progress and so the game can't be finished. Nothing appears on the radar, and no amount of calling or driving around will cause a radar blip for any sort of mission to appear - the only real fix is to reload from a save, although even that might not save you.
Like Oblivion, some quest-critical NPCs are invincible, but some are not and can die when wandering the Wasteland. Especially once you start seeing deathclaws and packs of radscorpions as random encounters.
The infamous Lamplight Vault Access Bug: as the main quest progresses, you discover that a critical Vault's main door is inaccessible (That door isn't even connected to the actual Vault map). Instead, you have to get in via Little Lamplight. But THOSE accesses are blocked until you unlock the proper dialog with the proper NPCs, even if you find the NPCs independently. Fallout 3 is so open-ended that it's possible to complete the quest that unlocks one of the dialog paths before you find Little Lamplight, or you might find and talk your way into Little Lamplight before the main quest fires the need to go there. If you do either of these things, then BOTH dialog paths are pre-empted from the game as if they never existed, and you can't complete the main quest at all. You'll likely be hours of gameplay and dozens of saves down the road before this bug rears its ugly head. The only known solution is to fire up the console and use a clipping cheat to move past the barriers.
A more standard one - load up on Rad-X, Radaway and the best hazard suit you can get, then try to get within discovery distance of the irradiated Vault itself (the place it will lead you does unlock a new place on your map). But unless you brought more than 300 Radaways (you'll need three a step even with the strongest hazard suit, Rad-X, and the radiation immunity perks, and it's 50 steps through the toxic area), you're dead. And if you set the game to quicksave when you find a new place, your file is now permanently [[Unwinnable]]. If you happen to try to quicktravel to a less toxic area, then you'll be DOA.
At least one NPC in the city of Megaton will occasionally commit suicide while the player is out of town or asleep. He has a tendency to go for strolls on a difficult-to-reach roof area, and will sometimes fall and die, taking his quests and rewards with him.
The Pitt shipped with a bug that froze the game instantly when approaching the Downtown area. This was so bad that Bethesda pulled the content from the Marketplace to fix it.
There are also numerous physics and architecture glitches, both outdoors and indoors, that can cause your character to become stuck in various places and rendered permanently immobile, forcing you to load, quit or cheat and noclip out (if you're playing on PC). It's enough to make you extra careful not to run into certain nooks and piles of rubble, especially if you're playing the console version.
The game gives you the impression that you can take your time on the "Scientific Pursuits" quest (aka the search for your father) when in fact putting it off after other quests will make the game Unwinnable due to certain game design glitches and you won't even know it. You're asked to "search for info about your father" that will "reveal the location of Vault 112", but the lack of specifics have a high likelihood of throwing you off.note For example, the quest log won't tell you the specific location of the necessary tape(s) (the Jefferson Memorial) nor will it tell you where to go once you've found the right one (you have to listen to the tape itself, marked only by number, and set the quest to "active" to display the marker) You'll probably end up looking all over the wastes for Vault 112 and/or the necessary resources to find it, including getting the Vault locations from the Vault Tech Headquarters, or getting the Explorer Perknote which reveals all of the game's discoverable locations (this Perk becomes available at Level 20, the base game's maximum). Neither of them reveal the location of Vault 112 on your map, and it's easy to look in all the Vaults for more clues since, well, what better place to find info on Vaults than other Vaults? If you go to Vault 87 you can complete a quest that you're not supposed to complete until after "Scientific Pursuits", and if you do so you'll end up unable to get inside the Citadel or the Jefferson Memorial rotunda lab, two locations your quest marker will point you directly towards. And you won't even know until you've spent at least an hour or so rescuing your father from Braun's simulation, taking a round trip through Rivet City all the way to Jefferson Memorial all while rummaging through some story exposition.
It is possible to become permanently sealed in Vault 106 with no legitimate means of leaving. If you close the vault door behind you as you enter there is no option to open it from the inside, causing you to be trapped forever.
Mothership Zeta has a fatal bug that may cause you to get stuck on the Observation Deck: Sally is supposed to crawl through a vent and open the door from behind, but she just stops there, either at the observation window or behind the door. This is because Somah sometimes doesn't teleport up to the deck from the Engineering Core, resulting in the required scripted dialogue failing to activate. This seems to consistently affect a given saved game, so the only solution is to reload an older save and hope it doesn't happen again.
Another oversight can cause the House quest line to be stuck at the sixth part if you gain infamy with the NCR, and by this time, you'll already be banned from both their and Caesar's main quests. Your only option now is to go Wild Card if possible.
Doing the quest "How Little We Know" too early (i.e. before being assigned it by Liza O'Malley) makes the main NCR quest, "For The Republic, Part 2", unwinnable, thus making the game unwinnable if you've been locked out of the other paths.
In Old World Blues, if you choose the wrong speech option when talking to your brain, you get stuck in an infinite dialog loop.
One area in the final level of Psychonauts features an Advancing Wall of Doom that requires you do a lot of fancy jumping to avoid it, using all of your different jump techniques. However, a seemingly random bug can activate in this part of the level, where your double jump refuses to work... dooming you to a watery grave.
Beyond Good & Evil is notoriously prone to game-breaking bugs that will end your progress if you save after encountering them. The most common is the dreaded "lost partner" glitch, where Jade's NPC ally will either fail to spawn where they need to, or become incapable of doing a certain action that's required for you to continue. In particular, during The Very Definitely Final Dungeon, if you attempt to backtrack right after releasing Pey'j from his crystalline prison but before spying on the Big Bad's meeting with his Dragon and taking a picture of them, you are guaranteed to get stuck. Definitely make a note of backing up your save data before you fly the Beluga to the moon.
One area has an enemy that drops a necessary key when defeated. However, a bug occasionally causes the key to spawn in the wrong place, making it unreachable. Worse is that the spot where this happens is right next to a save spot. A player unaware that they're supposed to be picking up a key might save after the fight and find themselves stuck.
Also, if you don't take Pey'j's Boots from a Locker, then you can't go back and get them later when you need the randomly generated code to get the spaceship you need to finish the game.
In Graffiti Kingdom, the fight against Telepin can be literally impossible if you haven't caught on to some completely-unexplained-but-necessary-to-know game concepts [such as swiping monsters with Pixel's wand giving you access to their attacks]. Before then, it is difficult, but entirely possible, to get through the game with only the basics. Not truly unwinnable, as you can remedy this by going back into the level to grab some better moves, but it definitely seems that way when you're playing the game for the first time. Many players simply give up and never play again.
Bubble Bobble Revolution for the DS has a glitch that causes the boss to not load in Level 30, making the game Unwinnable. The bug was fixed in the v1.1 release.
The series's autosaving also often lands players in unwinnable situations — for example, without enough ammo or the proper weapons in a battle. A particularly infamous example is on "Truth And Reconciliation," where a checkpoint sometimes activates just as Keyes is being killed.
"We're screwed! We're screwed, man!"
In Halo 2 and onward, after being stuck in an unwinnable autosave situation for a few deaths, the game will punt you back to an earlier autosave. If you find yourself in a situation that is possibly winnable but incredibly difficult, then multiple suicides to trigger this might be a good idea. Unfortunately, if you get yourself into an unwinnable situation that (if it was by Design) would be Cruel or worse, then you might live long enough for the system to autosave twice after you trigger it. The games' mercy has limits.
In Halo 3, at the end of the game, you have to race to the ship on a warthog while the planet ring is about to explode. There are a few different check points, most of them on the solid parts of the route. But there is one check point right before the final stretch where you can land at an odd angle, just as it is starting to collapse, and you then fall to your death below. The result is that you get stuck respawning upside down over a pit.
In Halo: Reach's New Alexandria mission, if you stay at the top of the Sinoviet Tower to kill the Drones, then take the elevator back down (or go back up then try to return), the doors at the bottom won't open, forcing you to restart the whole mission, since the game autosaves at the top of the tower.
The Chip 'n Dale Rescue Rangers game on the NES had a Game Genie code that would make you invincible, but did not prevent you from being stunned by attacks. See, in the game, being stunned and being damaged were two completely different things, and the code caused you to always become stunned instead of taking damage. The result was that if you got caught in certain areas where you were rapidly attacked or if you touched a stationary enemy, you'd be stuck. Interestingly, the Game Genie manual specifically warns you about this in the code's description.
The original Diablo disables the "SAVE" option when you die. However, it does so a few frames late, and during these few frames it's difficult, but possible to save already dead and watch your character die instantly each time you reload. There's only one save slot. While you can start the game over with your character's current stats (much like a New Game+, except accessible from the very beginning), you'll lose anything you had left lying around in town (which is likely to be a lot, due to Grid Inventory and Nothing Fades). But hey, it's your own damn fault for saving when you knew you were dead.
You can just plain save while surrounded by monsters and one hit from death. This is obviously user error. Another variant is to save immediately before getting dealt a final blow such as by a projectile, which is more of an accident.
This can screw up first-time Diablo players who come from Diablo II. In Diablo 2, you CAN save and exit when you die and get away with it. In that game, you will be brought back to town carrying whatever was in your inventory when you died. Anything on the ground or that you dropped(potions, usually), were gone... If you're used to that, the change in save-after-death in the original can burn.
Multiplayer characters can screw up in a different way: there is no regular save function and dying in multiplayer mode causes your items to fall to the ground. If you die in a place where you can't get them back (there is one notable enemy type that ignores the safe radius around level entrances and is also invisible, so you can die very quickly after entering a level, only to see a mass of hidden ones manifest around the stairs) and have no choice but to leave the game, you lost all of your items permanently. Good luck completing the game after that.
Diablo has strong roguelike influences and can screw you over in numerous other ways. Black Death in particular take away 1 hit point permanently on striking (with no indication that this is the case) and can render the game unwinnable if you are playing very badly and get hit hundreds of times, leaving you with a tiny amount of health. You have to try really hard to make this happen, though.
In Diablo II, if you lose everything, then you can still go back to where you died and pick up your body. Since it's a pain without your best weapons, you may decide to just quit the game and reload it instead. Doing this too many times causes the game to say "Bad Dead Bodies". There is no indication anywhere that this will happen.
Why people run into the "Bad Dead Bodies" problem: if you die multiple times, pick up your first corpse with all of your items on it, but don't have enough inventory space to equip them all, the remainder stays on your corpse. If you then die again, then your items are now split among two corpses. The game only saves the corpse with the most valuable items on it. Some useless items have a grossly inflated sales price. This may not literally make the game unwinnable, but losing almost all of your items in Hell difficulty can end your quest right there. This is considered a feature and it is the reason why most people simply quit and reload when they die once, and pick up their corpse in town.
The 7th Saga. Don't fight Valsu over level 40, when he could know the game breaking Elixir spell. Also, it's possible, after fighting Gariso, to be stuck in an area with monsters too tough for you to handle, so don't fight him until you're at least level 35.
In Atelier Iris 2, the item "Flay Hammer" is required to proceed at a certain point in the story. If you do not have it already, you cannot learn how to make it at this point, so the game becomes unwinnable. To be fair, it's so difficult to miss that you'd have to go out of your way to avoid having it by this point.
In Atelier Annie, events are triggered by entering locations; all but the final assignment, the Cosmic Conis, will be given to you even if you arrive late. The last assignment will only arrive if you leave your lab and re-enter it on a specific date, and if you don't, you'll never get it, even if (because you only have a few weeks left before the contest ends) you spend that day holed up in your lab. You have to be able to leave, and come back in, in order to trigger the event. Since there's no indication that there even is a final assignment after the last monthly one, because it's a plot event that's not part of the official contest, it's possible to play through the game several times and never know why you keep getting the bad ending.
In The Dark Spire, it is possible to advance the One-Winged Angel's quest line before obtaining the key item Angel's Bracelet. This causes the player to be unable to obtain the key item Black Orb, rendering the game unwinnable.
In the original version of the first Samurai Warriors game, there is a level where you must accompany Goemon to an escape point within a certain time limit. There is a nasty bug in two-player mode: if Player 2 reaches the endpoint before Player 1, then the ending will never trigger and you will be stuck standing at the escape point with Goemon until the time limit runs out, wondering what is going on.
Anyone who doesn't know how to race swoops should never play the first game using autosaves alone. The game autosaves at loading screens at set intervals. It may autosave in a position where your swoop is just about to explode.
There's an interesting glitch called the "galaxy droid" that gives you access to a debug menu that allows you to reach any area. If you go to areas that you should not be able to reach, then you may not be able to leave.
Choosing Mission to rescue you on the Leviathan can cause what's known as the Carth Glitch. If Mission is stealthed when she sets everyone free, then the game will hang during a later cutscene while Carth is talking. Carth's mouth will continue to move, but the scene will never move on. This occurs because Mission is supposed to talk after Carth but, since she's stealthed, you can't detect her. If your Awareness is high enough, then you may eventually see her and the game will then continue; but few people choose to level Awareness on the Player Character.
The Game Boy original version of Star Wars: The Empire Strikes Back included an unwinnable situation in the first level. Near the end of the Hoth caves stage, there was a long jump that needed to be crossed, with a stack of ice blocks on the other side allowing you to reach your destination. However, the ice blocks are destroyable, meaning that if you accidentally break enough of them (particularly by riding your Tauntaun while attempting the jump—it's weight automatically breaks through ice blocks), you are stuck with no possibility of finishing the level. Possibly Unwinnable by Design.
In the Game Boy original Star Wars: A New Hope, you can find each of the main characters from the movie (except Chewbacca and C-3PO) and add them to your party. However, you don't need to find any of them except R2-D2. Obi-Wan Kenobi is located in the back of a cave out in the middle of nowhere, and is notable in that he provides you with the less than useful lightsaber and also has the ability to heal your party a certain number of times. However, if you left Obi-Wan to rot on Tatooine then you'll quickly regret it upon reaching the trash compactor level of the Death Star. The sewer monster from the movie is seemingly immune to your blaster, and even if it isn't the damaging water rises too quickly for you to kill it that way. The only way to get past the dianoga is with the lightsaber provided by Obi-Wan.
In the NES version, you have to get certain things on Tatooine before leaving the planet in the Falcon. You have to at least get R2-D2, but unlike the Game Boy version, the lightsaber is obscenely useful, so you'll probably get Obi-Wan, and you have to get Han to leave. You do not, however, have to explore all the seemingly useless caves to find the little shield pick-ups. Failure to get any of these means that the Falcon turns into a one-hit wonder during the piloting sections, which are among the most difficult in a game that's already Nintendo Hard. Assuming you actually manage to survive the asteroid field that you encounter immediately after leaving Tatooinenote Difficult due to seemingly random, unavoidable asteroids, but not technically impossible, then you'll make it through the extremely difficult Death Star platforming sections (including 3 bosses) and immediately run into the TIE fighter escape from the Death Star piloting sequence, in which it is almost impossible to not get hit at least once.
Evil Dead: Hail to the King contained a particularly frustrating unwinnable glitch. At the start of the second disc, you're supposed to save the game at a save point immediately upon arriving in Damascus, then leave the area, fight some skeletons for the parts needed to open the town gate, and then proceed. If you do this, then reloading the game if you fail triggers the second disc's opening cut scene, and all's well. However, if you run to the area with the skeletons, then turn back around and then save the game and reload it, the enemies will vanish - along with the items you needed to collect from them. You're now stuck outside the city with no way to get through the locked gate, and with the game saved at that spot.
The two most common ways to make a game of Glider PRO unwinnable are to accidentally miss a star (backtracking is sometimes impossible) or to run out of a necessary powerup, especially helium (powerups are in limited supply, never respawn, are sometimes mutually exclusive, and can be drained all at once by microwaves).
There are several vents and transporters in "Slumberland" that let you skip large sections of the house. One of them lets you skip the sewers, which is a great relief except that one of the stars is down there, and there is no way to go back. It appears that this star was originally supposed to be in the room "You Got It," which is where the sewer route converges with the shortcut.
In the console version of The Sims 2, one of your objectives in the alien crash site is to "meet an alien". If you have previously met both of the aliens living here, it is impossible to complete the goal, which is required to progress in the game.
Treasure of the Rudra. A certain sidequest can be done right after a bridge gets broken. You're supposed to get on with the plot a bit first, and stumble upon the sidequest location in the process. Doing the sidequest as soon as it's available will land you on the other side of the broken bridge... with no way to get back.
In Desperados 2: Cooper's Revenge, there's a level with a sheriff NPC which you are not supposed to be able to kill; due to a bug, you can kill him. Speaking to this NPC triggers a mandatory scripted event. But if you kill him before talking to him, then the scripted event will never happen and the level (and thus the entire game) becomes unwinnable. The worst thing about this is that it doesn't become clear immediately; you may play for a long time wondering why nothing is happening and overwriting your save files. If you didn't have a save from before killing him, then you'll have to restart the enormously long level from the start. A published patch is supposed to fix the bug, but it doesn't.
The golf minigame Spheda in Dark Chronicle (Dark Cloud 2 in North America) can be made unwinnable via a bug in the Randomly Generated Dungeons design: after clearing the level of enemies, the game will spawn the sphere and the "distortion" (the hole) at random, then calculate the number of strokes you can make as a function of the distance and the number of walls between one and the other. Unfortunately, sometimes the two objects would spawn close to each other, with a single wall in between... but to get there, you'd have to traverse the entire floor. The game would then give you 1 stroke to sink the ball. It's even worse when Spheda spheres will change color whenever they hit the floor, the ceiling, or a wall, so even if you can make a miraculous U-turn shot, chances are the ball won't be the right color and will bounce off the distortion.
Thankfully, any given level's Spheda can be replayed by beating the level again.
One level of Marathon 2: Durandal has a pattern buffer (save point) over a pit of acid which just so happens to be unescapable.
One level of the first game had a pattern buffer in a secret room with a one-shot timed door. Don't save here.
Some levels, such as "Colony Ship for Sale" and "Ingue Ferroque", require you to shoot switches with grenades or fusion overcharge shots. Don't have grenades or fusion batteries? You're stuck for good.
Using the "skip to level" cheat may doom you here as well, since starting a level this way only gives you a magnum and no other weapons. (Those trying to beat the game using only their fists use Physics Models (mods, in other words) to make magnum bullets activate switches when absolutely necessary.)
Some one-shot door switches, such as in G4 Sunbathing and certain game mods, can accidentally be deactivated before the door is fully open, preventing further progress.
In the creature stage, your first nest could be in the water. Trying to swim to shore got you eaten by the sea monster.
In the tribal stage, your chieftain might randomly float miles up in the air, making it impossible to do mission-critical things that require the chieftain.
In the space stage, the spaceship you're sent to scan after you leave your planet sometimes failed to spawn. Since you need to scan it to get the Interstellar Drive and leave the star system, proceeding was impossible.
Half-Life 2 can be rendered unwinnable. In the museum where you have to deactivate three dark matter generators, the way to one of them goes through a room full of laser beams. As soon as you cross one, the door closes and you get mowed down by turrets. If you throw a painting from the outside corridor through the laser beams, the door locks permanently.
Even if you manage to destroy the turrets, the door won't open so you have to reload your game.
Averted in Episode 2, where the commentary states that they designed the autosave system not save in dangerous places during the strider battle.
The coin-op game Trog features four cute claymation dinosaurs (Rex, Bloop, Spike, and Gwen) collecting eggs and trying to get home. It has a complex egg-laying pattern (presumably this means "sophisticated", not "driven by the square root of -1") that sometimes fails to spawn the last egg for a particular dino, making it impossible for that dino to win the round.
The trading/combat game Elite has one star-system, Oresrati in Galaxy 8, which is over 7 light-years from any other; hence, it is only reachable by Galactic Hyperspace (or the "unlimited hyperspace range" hack). It's of insufficient tech level to sell you another Galactic Hyperspace. If you're not using the "unlimited hyperspace range" hack and don't have a recent saved position, then you're basically screwed.
Overlord used to have a bug in the brewery level where, if you left the level by any means before repairing and turning a wheel that activates an elevator to the lower floor, the items needed for it would disappear. Since going down was required, this made it impossible to continue the game. The game autosaves at all level transitions; unless you had multiple saves, it would be impossible to reload. It was fixed in a patch that thankfully also restored already Unwinnable saves.
Near the beginning, you pick up a scrap of wallpaper, which you eventually need in order to draw a map. Some time before this, you have to light a bonfire, and can, if you choose, use the wallpaper as kindling. The game doesn't try to dissuade you, and you can continue unhampered until you realise what you were supposed to hang on to the paper for...
It's possible to slide things you need into the slot at Annie's office before you have the item that motivates her to contact you; since the door doesn't open, you can't get them back, so you're screwed.
Call of Duty 4 has no specifically unwinnable points, but given the way the game sometimes autosaves in the middle of fights you can come pretty close.
Some computer versions of the classic 14-15 puzzle have an inappropriate shuffle routine (one which lays down the tiles in just any old order, instead of taking the space on a random walk through the tiles or swapping an even number of pairs of tiles, either of which procedures guarantees a solvable position) and thus generate an unsolvable position in 50% of cases.
Similarly, most implementations of Shanghai just lay down the tiles any old how, usually resulting in an unsolvable position. Fortunately, some (most notably Kyodai) are far more considerate of the player.
Champions of Norrath had this issue with a boss fight in the first chapter. To reach the Spider Queen boss, you have to bring a NPC to the door of the boss chamber. The NPC opens the door in a cutscene, and once you enter, the door locks you in for the boss fight, also done in a cutscene. Nothing too bad so far. After beating the boss, a door to chapter 2 opens and, like most bosses in the game, she drops equipment, and since there's a good chance you can't wear some it, the logical thing to do is take it and use a Gate Scroll to teleport back to town and sell it. Still not a big deal, since you can Gate Scroll back to where you used the first one. The problem comes when you either use another Gate Scroll out of town or use the teleport pedestal to do some more adventuring. The old Gate Scroll jumping point gets deleted, so you can't Gate back, and since the door to the room opened and closed by cutscene, the player can't open the door to the room, effectively locking you out of chapter 2 permanently.
Some (but not all) Windows copies of Chip's Challenge have a bug in Level 88 that effectively renders it unwinnable, due to increased aggressiveness of the walker enemy. This would later become known as the "Spirals corruption". Fortunately, failing a single stage enough times gives you the option to skip it.
Hexen version 1.0 had a bug (an error in one of the action scripts — it checked that the number of Green Chaos Serpents left on the level had been reduced to exactly 3, instead of to the intended less than 4) that caused the Episode 4 end-of-episode boss to sometimes fail to appear, leaving the player stuck in a sealed room with no way forward or back. This was fixed in version 1.1.
If you choose to save in the middle of the timed final level in Donkey Kong 64, you will return to find one of the Banana Medals can't be collected. You need all the Banana Medals to see the entire ending. Before YouTube, this was one nasty glitch.
One of the Golden Bananas requires you to enter a mechanical fish and shoot out 3 lights surrounding its heart, which are blocked by a propeller that spins/stops on a set pattern, in a certain amount of time. This is normally a fairly easy one to get. But if you don't do it by a certain point it becomes nearly impossible to get due to a bug that makes the propeller spin longer than normal. The only way to get the banana is to exploit a glitch that allows you to hit lights that are being covered, but this is difficult to do and doesn't always work.
The Sega MegaDrive / Genesis game Chuck Rock had a pit in the last level. There's a rock in this pit which you can place next to the wall and climb out. If you manage to throw the rock out of the pit, then that's it. You have to restart the game from the beginning.
FEAR: Project Origin, unlike the earlier games in the series, doesn't allow for any manual game saving by the player. There's only an automatic checkpoint system which doesn't allow the player to revert to earlier checkpoints. If you find yourself up the creek without a paddle, then you have to restart from the beginning of the level... and some of those levels are long.
A minor one in the first game (that got patched later). The game leaves logs for back story in laptops. One of these laptops is actually a mission objective, which you can see before you're told to download the log. Unfortunately, once you download it, you can't re-download it and you'll get stuck. Fortunately a patch later fixed this so that if you downloaded the laptop earlier, the character in the cutscene will mention that you already have the log, thus preventing you from getting stuck.
In The Forgotten, due to a somewhat fussy mouse control over a secret drawer, the player could end up skipping over a key required to enter a room on another floor. So when they enter the elevator, and use another key they found to release the safety so it crashes into the basement. Well Congratulations, you're missing the key item to end the game and now the elevator's broken, so you can't get back up. (Yes, there is a reason why this planned 7-part series only got the first game out)
One of the Dark Daxter levels in Jak and Daxter: The Lost Frontier can end up like this; no idea why, but going through an autosave point at a bad time can result in Daxter finding himself with no spiders to use to clog up holes in the ground, and not enough dark eco to smash through a wall.
LucasArts' policy was to be far more merciful than its competitor. But in The Secret Of Monkey Island, it was technically possible to spend all your money in the grog machine, one coin at the time. It was also possible to burn an item you'd need later, though later versions fixed this. A guide, past knowledge or brute force using player can bypass getting a map, only to be stuck when they are required to use it as a fuse.
The indie adventure game Pleurghburg Dark Ages attempted to avoid all unwinnable situations; the game is never supposed to be unwinnable under any circumstances. Still, one thing slipped; if you entered the park at night without the whistle and are about to be attacked by the panther, you're stuck.
There is one sidequest in Dragon Age: Origins in which you escort a blind templar through a building and fight a couple of demons along the way. There is a cutscene that triggers after you kill the first one, but if you get impatient and talk to the templar before it happens, you end up stuck in that room - the only two doors out are both locked and impossible to pick. Luckily, the game autosaves at the start of the area, so you won't lose much game progress by resetting.
Duke Nukem: Manhattan Project has an odd one relating to the autosave, where repeatedly dying in a certain location constantly resaves a fraction of a second later, leading eventually to you starting over a pit and dying every time you load.
Lemmings Revolution features a glitch in one level which makes it impossible.
At least one level in the SNES version of the original Lemmings was impossible to beat due to the timer being too short to save all the lemmings. The only way past is to use a password.
There are many, many versions of the original Colossal Cave Adventure out there. They form a convoluted family tree of ports to other platforms, ports to other programming languages, modifications to make the game more "interesting" (which may or may not work), and so on. One particular branch has a bug that makes the game unwinnable: instead of being able to "get spices," you get told "You can't be serious" if you try. Spices are one of the game's treasures. If you can't collect all the treasures, then you can't unlock the endgame. If you can't unlock the endgame, then you can't complete the endgame. If you can't complete the endgame, then you can't win the game.
In Blaster Master, you get a weapon upgrade for your tank which allows you to blow away certain walls, which will respawn after a couple of seconds. Should you get out of your tank and walk through a passage created when your tank blew away a wall, you will have no way to return to your tank after the wall respawns. In some places such as Stage 6, you can blast through the ceiling, but can't get out when the blocks respawn as you can't shoot downwards, and in other places you can get stuck without Hover power. There are a number of places where you also can't kill yourself, forcing you to reset the game.
Level 4 has an innocent looking one, until you actually get into it. It's just a smallish dead-end hole that looks like you can jump out of... but it's one tile too deep to make the jump. You need to hover out. If you don't HAVE any hover power left, only one button will save you now, and it's not located on the controller.
Strife: Quest for the Sigil has a few intentional unwinnable situations, but there's one case of Unwinnable by Mistake that only shows up if the player cheats: The Front base's location is dependent on how many Sigil pieces you have. If you have even ONE sigil piece, then the Front base is moved to the castle. Problem? If you cheat to get the Sigil early, then you won't have access to the castle and won't be able to get ANY ending without further cheating because Macil, who gives you all the key jobs (except the first one) until the Front base moves, won't be accessible anymore.
There's another which can occur without cheating, but it's very rare. The plot path requires that you destroy the computer in the Administration Complex; the plot says that this lowers the forcefields protecting the Administration Complex and the Bishop's Tower, but what it actually does is to unlock the exit back to the Bailey, and a switch inside the door back to the Bailey is what actually lowers the forcefields. Which is fine if the teleport from the Administration Complex takes you to the other side of the door; but if it glitches and sends you back to the Gatehouse where you first entered the Bailey, the forcefields will still be up leaving you stuck. Nor will re-entering the Security Center to get through to the Administration Complex again work, since the bars which opened to let you through have closed again.
In LEGO Indiana Jones, it's possible to make a level unwinnable during certain mounted segments. Riding an elephant into a insta-death pit, for example, causes the player character to die shortly thereafter, at which point he respawns at the last "safe" point - back on top of the elephant, still in the death pit.
In LEGO Star Wars II, the "Jabba's Palace" level has a pit that cannot be escaped. However, there is also nothing to kill you, so you must simply restart the level.
If you were looking for one hundred percent completion, you need all the character icons, school crests and students in peril. Good luck doing so if you exited the fat lady without grabbing everything, and then tried to reenter as any character other than a Gryffindor by mistake. The portrait glitches and permanently seals, where she will wave at you, but the option to recite the password is lost forever. Extremely annoying if you spent hours collecting every other token before realizing the glitch had occurred.
There's an entire FAQ written specifically to identify and help avoid the heaps of game-breaking glitches in this game. One particular bug of note occurs in a section of the game that takes place under one of the game's classrooms where you have to go to grab some of the collectibles in the game. At the end of the hallway, a Lego dragon tosses you upwards back into the classroom — Except, sometimes he misses the throw, at which point you are stuck permanently in that section of the game and cannot continue. If you reset the system, you "only" lose all your progress since your last save. If you instead try to circumvent this by saving, you've just hosed your save file. The game will always load in this corridor with a dragon who will not throw you, and you have to reset your game file to complete the game. Way to go, QA!
Worse still, the game becomes almost impossible to go over 70% completion if you're playing Co-op, at one point in the game you complete a class but never unlock something from the class, you also get no indication that the class was where the unlockable was meant to be unlocked, this leaves you playing the rest of the game assuming that you'll unlock it later only to find that you don't unlock it and simply cannot entirely for the reason that you were playing Co-op.
LEGO Jurassic World has a very frustrating and easy to trigger glitch that can render the Gyrosphere Valley level unwinnable. At one point is a see-saw that, if you drive across and off of it before Gray wanders onto it, he'll stupidly wander under it and get trapped. You can't get back onto the see-saw, you can't advance without Gray's abilities, and you're forced to restart the level. This is guaranteed to drive completionists bananas since there's several very difficult to grab minikits in the chase sequence prior that will have to be reobtained when you exit and restart.
Robin Hood: Prince Of Thieves for the NES had an item, The Druid Dagger, which was required to destroy an enemy late in the game. Midway through the game, Duncan The Blind leaves the party and takes all his inventory with him. If he has the Dagger then, you will probably be unable to get it again and will get stuck just before the final fight with The Sheriff Of Nottingham.... A bug in the character system does create a one-time-only instance of a character with a random name who carries Duncan's things; but once you pass by him, the character disappears, never to be seen again.
The horrifically broken password system in the game (it was hidden for a reason) would put Robin in the proper place but with a different inventory which is often missing anything of value, including plot-critical items. The password that took you to the final sequence would not give you the Druid's Dagger; the game is unwinnable if you use it.
A third instance: a 'hidden feature' allowed rapid fire in the sword duels simply by holding down Start. If a player jumped while holding Start, then Robin Hood would not come down from his jumps, allowing him to spring through the screen vertically and eventually wrap around. It was possible to get wedged into the floor and be unable to jump any more without an apparent reason. The player would now be too low to hit the other sword fighter and too low to be hit themselves, which makes the fight a complete draw. You can't back out of the duel, and so the game has to be reset and started over from the beginning. (We did mention that the password system is messed up.)
The Harry Potter And The Chamber Of Secrets game autosaves when you enter the Chamber of Secrets. Problem is, you really need lots of health potions in there, and you can only get health potions by making them in school before you enter. Oh, and there's no way out once you're in.
In Commander Keen Episode I: Marooned on Mars, if you beat a level with a ship part without collecting it, you're screwed as you cannot re-enter levels in the game.
If you play Commander Keen Episode V: The Armageddon Machine on Easy difficulty, and enter the secret level "Korath III Base", if you're running the original version of the game it will crash as soon as you enter this level. The bug-fixed version does not have this problem, but the fuse which you're supposed to break in order to get the alternate ending to the game is not breakable on Easy difficulty. Either way, if you're planning on visiting the secret level, make sure to play on Normal or Hard difficulty.
Unpatched versions of the original Descent have a Game-Breaking Bug that makes the last boss unkillable on any difficulty level except the two easiest ones (out of five).
Jake Hunter Unleashed has a particularly insidious one in the last chapter. At the beginning of the case, you get an option to pick your partner from three characters: Yulia, King and Sam. Choosing Yulia makes it so you cannot access the critical "deduce" option later, thereby preventing you from finishing the case.
Many, many amateurly programmed adventure games, especially using the RAGs developer, can have this. One example that comes to mind, is one where the person accidentally coded the ending trigger wrong, so a filler conversation would always trigger, as opposed to the actual ending. (Checks for Variable: Leaf Fairy, followed by variable: Negotiator Fairy. He coded the variable to become Negotiator Leaf Fairy, so the first part is always triggered!)
There is a similar example in My Bloody Fairy Tale, where you are required to gather a number of magical items and a magic code to activate a transformation spell, allowing you to get into the next area. But the magical items are used up in the spell,and the code is written on each of the items. You are not reminded of this second fact after you've found the items, and infact, you're only told by a ghost after you specifically ask about it. So if you start the ritual before reading the code, the game is unwinnable.
In the version of FreeCell distributed with Microsoft Windows, game 11982 out of 32000 is unwinnable.
Windows XP and onward extend this to 1,000,000 games. The same seed-based RNG is used, so as above, 11982 is impossible. Including that one, there are eight unwinnable deals. 146692 is the second one.
Taken even further, 1282 out of the first 100 million deals are unwinnable, which is one out of every 78,003.
Some versions of Ratchet and Clank allow the player to skip a vital gadget midway through the game. Planet Orxon is initially played as Clank, as it's polluted by toxic gases that Ratchet can't breathe. As Clank, you're supposed to collect the Magneboots (allowing Ratchet to scale metal shafts), before getting the coordinates to a planet where you can acquire an oxygen mask. You're then supposed to return to Orxon and, as Ratchet, use the Magneboots to complete a mission. If you missed them as Clank, you can't get them.
Penny Arcade made two otherwise nigh perfect games, but at one point it's possible to hit an unbeatable snag. After being forced into the mental institution, you have to shock your brain back to health. The second and third levels of this mini-game feature unrotatable blocks of damaged tissue; if one of those blocks is at the edge and can't be reached, you have no choice but to quit and reload.
Just like its remake, the original version of Baroque has voice and item lists, which have to be filled by talking to NPCs and registering items, in order to obtain 100% completion (and some bonus art). The lists can't be completed in a single game, so you have the chance to restart while keeping your database intact, in order to eventually get everything with repeated playthroughs. However, in what was clearly a design oversight, one of the voices can be missed permanently if you don't get it before registering 20 items. And restarting won't do a thing, since your game data and system data are separate. Your only option is to delete the system data and restart filling the lists from scratch. Made worse from the fact that this mistake is especially easy to meet, because the method of obtaining the voice is rather obscure (you must die three times in a row before talking with the Collector), and because 20 items are usually registered pretty quickly into the game. Good thing you don't actually need 100% completion to see the ending, but still painful for completionists. The problem was fixed in the remake, thankfully.
The 1997 Blade Runner PC game is unwinnable on modern computers without special measures because one encounter and one bomb are timed based on the speed of the CPU. Yes, computers are that much faster now.
Grim Fandango has a similar bug when you are in the elevator in the High Roller's Lounge in Rubacava. On modern computers the elevator moves too quickly to complete the puzzle, rendering the game unwinnable without patching.
After you solve the elevator sequence, it is possible to return to the kitchen and have Manny stick his scythe into the pantry door. Now, the first time you do it (as part of a trick to get into said elevator), Manny gets it back automatically. If, for whatever reason, you decide to put the scythe on the door again and leave it there, the game won't do anything to prevent you from completing the chapter and sailing away from Rubacava without it. This is bordering on Unwinnable by Insanity, since by then you should be very well aware that the scythe is Manny's most treasured item, but this being a LucasArts game, chances are you didn't expect to be able to screw it up and kept a single save file throughout the game. The kicker? The game has a programmed response for having an empty inventory, even though the only way to make it empty is to get rid of the scythe through the described actions (making the game unwinnable in the process).
On the opposite end of the spectrum, there is one mission in Saints Row: The Third where, after a cutscene, you will have to kill a brute. However, if you're playing on a slow computer the game will fail to load the cutscene, causing the brute to kill you before you can do anything.
The Shadowrun game on the Sega CD can end up being unwinnable as a combination of three factors: the game has only scripted battles, set points where the player characters gain experience and a highly customizable character building system. The end result of this is that it is entirely possible to build up your characters in such a way that they cannot win a mandatory battle, and the game offers no possibility of straying from the main storyline to grind.
You can get stuck between an NPC and a wall in Chapter 5 of Mother 3. Unfortunately, this game doesn't have the walk through NPCs workaround to get you out of there, so the only thing you can do is revert to an old save if this happens. The killer? The NPC you managed to get stuck behind is a Save Frog, meaning the last time you probably saved was right after getting stuck behind it, and due to a programming oversight, it will never move out of your way, effectively ending the game and forcing you to start over. The fan made strategy guide for the game advises that you avoid that save point completely and tough it out until you get to the next one.
The specifics of the Rock Band 2 star cutoffs mean that the score required to get a 5-star do not go up in direct proportion to how many notes are added - instead, the cutoffs take what is called a "base score" (every note taken at 1x, all sustains held to full) across all of the parts and multiply them by a number that increases depending on how many players (and which parts) there are. There are also two different challenges that strip overdrive from all songs in the setlist, one of which tasks you with getting five stars on every song in the setlist. Ace of Spades cannot be 5-starred with a full band unless overdrive is used. Biggest Show Ever adds Ace of Spades as an encore, strips away all overdrive phrases from the songs in the setlist, and penalizes you severely if you get a 4 star on any song in the setlist. Rock Band 3 uses a refined method which avoids these problems for stars, but it's occasionally impossible to get 5 spades on a song in the story mode, depending on the song, the number of players, and what you need to do for the spades.
In Vampire: The Masquerade – Bloodlines, it is possible through a bug that the slowing down effect of the fat Tzimisce things in the sewers of Hollywood will last for the rest of the game. That is not so much of a problem until you have to get out of a cave with a timed explosion, where it will be impossible to even get near your boat.
Also another bug caused the game to crash at the point where the video for said explosion is loading.
In some PAL copies of Digimon World, there's a glitch which prevents you from accessing a dungeon by stopping you from speaking to the guard who is supposed to run away and let you in. Not being able to get in there has the knock-on effect of barring you from several areas of the game.
An inordinately tough boss battle can be accessed by speaking to a certain character, then leaving his building via the only exit, at which point the boss appears. That building contains the game's only save point, and is where you respawn if you lose a battle. Some versions do reset the event under certain cirumstances.
Vision is a great escape-the-room game, but some players have found themselves in an unwinnable situation after failing to pick up the desert marble (the one marble that's the easiest to overlook and the least required for puzzle-solving) before going down the elevator and finding themselves without all the marbles required to complete the final puzzle.
Alone in the Dark: The New Nightmare had a frustrating glitch where a plot-critical item simply didn't appear. This happened way too often for the developers not to know about it. The only option was to grit your teeth and reset.
Medal of Honor 2010 has many bugs, some of which can induce unwinnable situations. For example, in Defend The Crash Site, you are defending a crashed helicopter from the Taliban with a minigun turret, and at a certain point, an enemy is supposed to destroy the turret with an RPG. Unfortunately, particularly in the PS3 version, this Scripted Event sometimes fails to activate, resulting in the mission continuing indefinitely. Another one happens in Belly of the Beast, where you're supposed to cover fire for your team mates as they advance, but again, the event flag for their advance often fails to activate. The only way around these is to restart the mission from the beginning and hope you don't get screwed again, and if that (god forbid) fails, restart the whole game.
In Lagoon, it's possible to save virtually anywhere as long as you're not in the middle of a boss fight, even if you're about to fall down a Bottomless Pit.
In the first three Syphon Filter games, you can trigger a checkpoint just as you're about to be headshot or otherwise instantly killed, or triggering mission failure, trapping you in a Cycle of Hurting. Timed missions can also autosave with too little time on the clock.
Fable III has a bug that can happen if you access the menu at some areas. Instead of simply opening up a screen with options, Fable 3's "menu system" transports you to your sanctuary, then transports you back when you're done. The bug in question causes you to be transported a few inches below where you should, causing you to fall under the map forever. Worst yet? The game auto-saves every time you leave the menu, and there is no disabling it. Try to re-open the menu to get transported and find another way out? You can't. You're falling, it's an action, and the menu won't open up during actions. Ironically enough, you can open the save/load screen and walk around the save/load room, but nothing else. The game also won't allow multiple save files for a single character. In other words: got this bug at the end of the game? Tough luck.
In the iPhone version of Bookworm, you have to collect words on various lists (body parts, vegetables, pets, etc). The word "Gold" is on the "Colors" list and the "Minerals" list, but you can't collect it from "Minerals" so you can't ever complete all the lists.
Anne McCaffrey's Freedom had a level in which the main character had to cross through a brief hazardous area that would inflict minor damage on her in order to reach a plot critical NPC and finish the mission. Problem is, if she was at nearly zero health and had no healing items, it was impossible to get her across the area. And any other party members with more health couldn't be substituted; the NPC would only talk to the protagonist.
There is a possible hiding spot from Bobby that can either turn into Unwinnable by Design or Unwinnable by Mistake depending on the game's mood at the time. Normally, it would be Unwinnable by Design (or a chance of such, anyways) for Jennifer to climb up the shelves in the garage to evade Bobby, and further kick down the ladder she climbed to keep Bobby from climbing up after her. After you pat yourself on the back for a clever idea, you'll soon realize, oh crap, Jennifer can't jump down, and Bobby further crashes your parade by crashing through from the ceiling to impale Jennifer, who now can't run away from him, killing her. On the game's bad days, however, sometimes Jennifer can still trigger these events even if she hadn't kicked the ladder down. Worse, sometimes Bobby can crash from the ceiling immediately after, standing between you and the possibly-still-accessible ladder to climb down, and even worse, corner Jennifer by making her back up toward the left of the screen while menacingly following her. The problem comes when the game further gets confused that the boundaries that should've stopped Jennifer to the far left of the screen aren't recognized as such, so instead of have Jennifer stop to be impaled by Bobby, she continues to back away well off the screen while Bobby follows her, neither stopping to do any escaping/killing and forcing you to restart.
There's also one escape point on the second floor that involves Jennifer jumping over a hole which Bobby can't make and instead falls. If you do this you have to grab the rope and tie it to the bannister to climb down to the first floor (since the gap is now too wide to jump; Bobby smashes part of it when he tries). However if you instead go into the storage room without using the rope, there's a 50/50 chance that either Bobby or a harmless cat will pop out of the crate. If it's Bobby, you're S.O.L: you can't interact with the rope in "chase" mode, there's nowhere to run, and when Bobby kills you you'll respawn in the room and immediately retrigger Bobby coming out of the crate (it's randomly chosen at the beginning of the game; it will always be Bobby if he popped out once), and your only option is to start your game over.
In Clock Tower: Ghost Head's second level, there are several zombies on the map which you can lead into traps that incapacitate them and allow you to escape, but most of them merely cause the zombies to return to the room where they were first encountered, and only work once. Not so with the broom in one of the restrooms, which has unlimited uses and causes the zombies to disappear permanently. However, while a savvy player can certainly use this to their advantage, there is a certain part of the level which requires the player character to change into their alternate personality Bates, and the only way to trigger this change is to get attacked by a zombie and escape. If you only cleaned out the zombies in the most critical areas, good for you, but if you took out every single zombie on the map, you're screwed.
In Epic Mickey, there's a glitch that can occur late in the game, activated if you ignored the machine on Skull Island. After completing Lonesome Manor and starting the quest "Oswald Needs Help", if you go to Ventureland and then back to Mean Street while that quest is active, the game will skip ahead in the story a bit. Not so bad so far, as you can continue the story like normal from this point. However, if you try to go to Ostown, the conflicting events will cause the game to permanently fade to black when you arrive. And since the game autosaves, you'll be stuck if you try to reset and reload.
In the Dream Forge game The Summoning, the door to the final level can only be opened if you possess 5 black and 5 white pearls. But the level before the door contains only 5 black and 4 white pearls. The only other white pearl is back near the entrance, 30 to 40 levels previous, and you cannot return there. So if you didn't pick it up, dropped it to save inventory space, or sold it, the game becomes unwinnable.
In the first BloodRayne the final boss fight is a three-way battle with Juergen Wulf and Beliar that lets you save after you kill either. The problem is the Beliar has a time limit and is quite hard to damage, so if you save after killing Wulf you might find yourself without the time to aviod the auto Game Over.
In Sword of the Stars some scenarios require you to colonise certain systems. Unfortunately, if those systems are already owned by enemies, your bombardment of the inhabitable planet may lead to it being out of your Terraformable range when the dust clears. To the load screen!
In the Playstation 2 version of Spongebob Squarepants: Revenge of the Flying Dutchman, a loading glitch prevents the game from working properly.
In WarioWare, in the needle-threading microgame on Mona's stage, sometimes the needle is placed too high or too low to thread it.
In Wing Commander Prophecy, your carrier is equipped with Imported Alien Phlebotinum that can be destroyed by enemy torpedoes in the third Hrissith System mission. Nobody will say anything about this at the time, but when you try to fly Mission #5 ("Defend our Imported Alien Phlebotinum!"), you will lose instantly - before your fighter has even launched. (Fortunately, the "Flight History Terminal" makes Save Scumming easy.)
In Zoo Tycoon 2: Endangered Species, trying to adopt a Galapagos Giant Tortoise would cause the game to freeze or crash for some players. One scenario in the campaign requires the player to adopt and breed these animals. Because of this, said scenario could be unwinnable for those affected.
In-universe example: In The Lost Crown: A Ghost-Hunting Adventure, Nanny Noah has Nigel playtest a clue-based treasure hunt she's designed for the children of Saxton. There's nothing preventing Nigel from doing so, but later in the game when the kids are supposed to play it, one of the locations they'd need to visit is locked up for the holiday, making it inaccessible and the game unwinnable.
Both Baten Kaitos games have remarkably similar situations in which the game can become unwinnable. In the first game, you can't escape the battleship Goldoba until Giacomo, Folon, and Ayme have been defeated, but there's no place to level up on the battleship, meaning you're screwed if you're underleveled. In the second, the Holoholobird attacks after a disk swap and a temporary Point of No Return, which will trap you in the Holoholo Jungle, in an area with no enemies to grind on.
In defense of the first game, Kalas warns you that you shouldn't leave Mintaka and board the Goldoba until you're absolutely ready. The second game, however, has no excuse.
The launch version of NCAA Football 12 somehow managed to omit Boston College vs. Virginia Tech off the playing schedule. However, the game's back end recognizes that it is there, and simulates the game without the player's input when you advance the weeks. Since even a single loss can put a team out of the running for a national championship and injures are FAR more common in simulated games, players can easily lose the game and be eliminated from title contention through no fault of their own. Or, they could win the game but lose several star players, which can have the same effect overall.
Unfair difficulty in the first Soldier of Fortune doesn't allow manual saving or multiple saves, so if you find yourself in a no-win situation (too little health and/or ammo, or the wrong weapons), you have to start the whole game over.
NetHack 3.4.3 (the latest version for several years as of this writing) has bug C343-424, which can render one of the Plot Coupons permanently unusable if you do the exact wrong thing with it. It's slated to be fixed in the next update (along with hundreds of other, less breaking bugs), but we're not sure when that will be.
This was a problem in the Fist of Guthix minigame in Runescape. Just like the rest of the game, players can only right click to attack other players that have a higher combat level. Because of this, all the hunted players would gather on one spot in the center and stack on top of each other. The lower levelled player would thus be presented with a large list of "Trade," Follow," and "Walk here" when he right clicked, and the option to attack his opponent would be pushed off the screen, making it impossible to click. As a result, a higher levelled player would acquire a large amount of charges that is nearly impossible for the lower leveled player to get. This happens less frequently nowadays due to fewer players in the game and an update to the right click menu.
Fahrenheit (Indigo Prophecy in the US) is a game that relies on a Simon Says gameplay. Towards the last half, there is a timing bug in the PC version (and sometimes the PS2 versions) of the game that will cause you to always fail, making it impossible to continue the story.
In order to reach The End dimension, you need to activate the end portal, found in Strongholds, which only spawn 3 times per world. Generation bugs can cause the portals to be incomplete, and if all 3 portals are incomplete, you're screwed.
Before the hunger bar was introduced, there's a possibility of getting stuck in a 2 block deep hole in Bedrock. Normally, if you have a supply of blocks this wouldn't be a real problem since you could create a platform under you to escape. However, if you for some reason fell into this hole without any blocks, you better hope there's an enemy mob nearby that can kill you because there's no way you can respawn without death and Bedrock is indestructable.
If you place lava on your original spawn point (the one not set with beds) and die, you will respawn on the lava, and die again, ad infinitum.
In Super Star Force, stopping the fountain in DA 0820 before completing the dungeon in DA 0001 makes the latter impossible.
Left 4 Dead 2 has The Passing campaign and a Scavenge Mode where the objective is to fill up a generator with cans of gasoline. Naturally, Valve made it where the cans respawn if they are destroyed. However, if a dropped gas can is near a Boomer that explodes, the can goes sailing high into the air, so it is possible that the flying can may land on a rooftop or some other structure that the survivors can't retrieve it from. Unless you have a molotov to hurl to the lost can to destroy it so it respawns in its original place, the game can't be finished. Luckily, this can rarely happen since the direction of an item that gets thrown from an explosion is pretty random. Dead Center's finale has the same gas can objective as well, but it takes place indoors and the survivors are able to access most of the map, so losing a can here is nearly impossible.
The Thing (2002) has a stage where the player descends a long staircase (similar to the staircase sequence in Metal Gear Solid), and has to deal with automatic turrets on every level, scalding steam vents, seemingly endless streams of scuttling creatures that pop out of dead bodies (and attack you from front and behind), and the medic, the only hope of surviving the stage, turns into a monster at random points. If the player doesn't have enough health packs, or enough firepower, it's impossible to get through the stage(though there is one way to make it easier, if you leave the medic near the top of the staircase and run back up to him to get healed instead of having him follow you, he dosen't seem to turn into a monster).
If you are on the top-right corner of the screen after you defeat Baby Face, and you skip the tally screen as fast as possible, Headdy may not have enough time to get to his spot, and if the tallies are gone before he gets there, the game will lock up. Here is a video.
There's a way to lock the game if you land the final blow on Clothes Encounters off-screen, with the Super Head. But if you wait for around 4 minutes, it'll eventually return to normal. Video here.
Virtual Corporation, an old PC game played via voice, will throw you out a window if you get too stressed. The only way to lower stress is to go on vacation. The problem comes where the only two vacations you'll be able to afford, the skiing and wind surfing, have QTE that no key can get past. If you don't complete it, your stress doesn't go down. Luckily, it's simple enough to go into your save file, find the stress value, and lower it, only buying automated vacations for the rest of the game.
In the original Just Cause the second-to-last mission involves chasing something down and destroying it in a super-fast jet. Some people assume the jet will be useless after this mission and feel free to bail out of their jet as soon as said target is destroyed. The game will then autosave while you're in freefall or parachuting to safety, and you will find out quickly that you needed that jet for the next mission. At best, the jet will be just out of reach of your grapple and zoom away into the distance without you. If you're unlucky, it smashes into the ground in a fireball. You then have no choice but to start the game again, as during these final missions you can't go into free roam and access the mission again that way.
In Puzzle Quest, it's possible to accidentally make the siege of Silvermyr unwinnable if you spam too many spells - the Magic Node (adds +5 to all skills when enemy uses a spell) will buff its skills to ludicrous levels (Battle 90+) meaning that any damage done to it will do nothing or actually heal it!
In Crystal Caves 3, one of the levels in The Hub is located down a deep pit, too deep to jump out. If you drop down into the pit before completing all the other levels, you're stuck. Thankfully, it is possible to leave via cheat codes.
Grandia II: In the first battle against Millenia (a Hopeless Boss Fight), the battle is scripted to end when Millenia casts her Zap! spell. She can get caught in an AI loop that causes her to never use Zap!, and it's impossible to end the battle in any other way (her HP doesn't decrease, and you can't escape the battle).
The Game Boy Advance version of Donkey Kong Country 2 requires you to play a mini game with Funky Kong in the first world in order to gain access to his flight services. If you're in too much of a rush to bother with this, it's possible to get to the Flyin' Kroc level but be unable to ever return to a previous one, making the persuit of 102% impossible.
In chapter 16 of Fire Emblem: Blazing Sword, you have allied soldiers fighting by your side. However, if any of them were still alive by the time you beat the boss, an allied soldier might end up occupying the throne before you could have your Lord seize it. Because of the nature of the AI, they wouldn't move from the throne to make way for the Lord. You also couldn't kill them, essentially making the level unwinnable and forcing you to restart, if you don't have either a unit with enough Build, or a Rescue staff and a unit capable of using it.
Fire Emblem: Genealogy of the Holy War has a number of scripted battles taking place between enemies and allied NPCs in several chapters throughout the game, the most popular examples being Mahnya's fight against Pamela and Andrei's combined forces and Travant ambushing Quan and Ethlyn as they trudge through the Yied desert. In most of these examples, one side is destined by the plot to lose, and generally have the odds stacked heavily against them to ensure that happens. However, it's possible, though exceptionally unlikely, for the "losing" side to end up winning the battle if the RNG favors them; if the player is especially careless or unlucky, this can result in them conquering a castle before the player can, locking the player our of the rest of the game unless they have a save from before the game engine defied the plot. The likelihood of this happening without player intervention (especially in the Yied Massacre example above) is slim, however, rendering it more an example of Unwinnable by Insanity.
If you saved the game during the Playable Epilogue you'd get stuck in it, unable to leave Lalivero and unable to do anything there but view the ending. This wasn't a huge deal if you were completely done with the game, but since you were stuck in Lalivero you couldn't go back and complete the sidequests or find Djinn you missed (and may have wanted to transfer to the second game). The worst part is, many players didn't even realize they were at the end of the game until the credits started rolling. The story clearly wasn't over -Saturos and Menardi were dealt with, but Felix and Alex escaped, Jenna, Kraden and Sheba hadn't been rescued, and you'd only been to two of the four elemental lighthouses. Many players' first thought after completing Venus Lighthouse would be to save the game... And in doing so, trapped themselves in the epilogue they didn't even know they were in. The sequels fixed this by making it impossible to save after beating the Final Boss.
Save after the Mt. Aleph boulder falls and Jenna's parents, Felix and Kyle supposedly die, then do the Sanctum cheat, (L, start and select) and congrats, You are in your room, you can't go back to Jenna's house because a boulder is blocking the way, Isaac is on his own, and you can't trigger the cutscene with Satorus and Menardi, and you can save after you do the cheat, and you'll have to restart the game.
The Lost Age has a near-miss if Piers is holding the Lash Pebble when you go to Lemuria, where he leaves the party and you need to use Lash without him to continue. However, the dev team caught this one: if you approach Lunpa's house without the Lash Pebble, he mocks you for your mistake before throwing you a rope himself (this is the only use of the "rope throwing" animation).
Computer Spider Solitaire can be rendered Unwinnable if you clear away almost all of the cards before dealing the last set (this is rarely even possible, but it can happen). The game won't deal any more cards unless all the open spaces are covered, and if you don't have enough cards in play to cover them, you're stuck. This can be solved by simply planning ahead, but it's a crushing way to lose, since just moments ago you were doing exceptionally well.
The "Killing Time" mission of Thief: Deadly Shadows consists of a descent from the top of a clock tower into the basement. The highest difficulty requires you to get all three pieces of "special loot" on every level, one of which is a diamond gear, found in the first room. However, unless you're specifically looking for it, it's difficult to spot, and likely to be bypassed on first-time playthroughs. Later on, you find a message that clues you in to look out for that particular gear, thinking that even if you miss it, you can usually just backtrack— but not in this mission. About halfway through, there is a big vertical chamber which is easy enough to fall down, but once you've done so, explored the rest of the level beyond, and cannot find the last piece of loot, you're better off restarting the mission, as the vertical chamber is virtually impossible to climb back up.
Several levels in the original game required lighting torches with fire arrows in order to complete. The problem is that fire arrows are rather rare and it was entirely possible to run out of them and be unable to complete the level. In the Thief GoldUpdated Re-release, the designers added an invincible "fire ghost" enemy that would drop fire arrows when attacked to these levels.
Vorador's Mansion, in Legacy Of Kain: Defiance, features a stained glass window that Raziel is supposed to blast out with telekinesis. However, in the spectral realm, the window doesn't clip properly when touching it from the outside, allowing a player to accidentally jump through it and into the upper floor when in the spectral realm. Unfortunately, the clipping does work from the inside and accessing the only exits from the corridor require being in the material realm, for which there are no conduits within the corridor. And the game can easily be saved within.
Due to glaring level design bugs, the final boss in Slave Zero is unbeatable at Hard difficulty: his HP simply exceeds the combined damage that all the ammo in the final arena plus those in your magazine can do. There are indeed other ammo pickups but they happen to be buried inside a wall, so you can't step on them. There is even a supply flier that drops bullet boxes; however the boxes, once dropped, miss the script that allows to pick them up (you just run through them). So you just unload all of your ammunition in his face, then either settle in the center tower (where his missiles cannot touch you) and wait for the end of the world, or you let him kill you in frustration.
The final few stages in Luminous Arc 2 can be cleared quite comfortably with your levels on par with the enemy, with a little intelligent strategy. However, doing so can land you at a Final Boss that's mathematically impossible to beat with any party combination thanks to its high defenses and HP regen. Fortunately it's easy to revert to a point where you can grind, but that means doing the preceeding three battles over again when you want another crack at it. Without any one-use items you ate up the first time, those aren't refunded either.
This would only apply in circumstances the DM chooses to make it apply; while the Paladin is usually not allowed to associate with evil characters or others who consistently offend their moral code, many dungeonmasters would allow a temporary Enemy Mine scenario to deal with a Bigger Bad. Especially when the plot demands it.
Legend Of The Seven Paladins 3 D is a Doom clone that is programmed so badly that the game runs insanely, extremely fast. Most of the time, players will only get a short way into the game without dying from enemies that fire at lightning speed.
In The Witcher, if a quest-critical NPC dies you cannot complete their quest. Well and good, except that it's possible for Vesna Hood to die after you've completed the Escort Mission section of her sidequestnote Specifically, bad luck with the enemy spawning code can cause barghests to appear and kill her between her porch and her house, after Geralt is done escorting her home., making it impossible to collect her sex card. Then, if Geralt allowed the Scoia'tael to take the smuggled goods in Act I, doing things in the wrong order in Act II causes a sidequest target to be assassinated by the Scoia'tael for drug dealing before Geralt can get to him.
Mabinogi's VIP inventory, in which Locks when VIP service ends. You can lock yourself out from various storyline quests by accidentally putting in Key Items. Overlaps with Unwinnable by Insanity.
This also counts as Unwinnable by Insanity since you have to do it on purpose, but in Tony Hawk games with a skate park creator and death traps, you can put a death trap in the exact place the player spawns in custom parks. However, this is actually hilarious since you have unlimited lives and respawn immediately upon death- you're in a "Groundhog Day" Loop of death and pretty much dying/respawning at a rate of once per second. Since this is a custom park, you can just exit it and redesign it, but the only way to stop the loop is to Rage Quit.
PAYDAY: The Heist has a system in place where if a player that is holding a mission critical item leaves the game, those items are transferred to the next player (bots cannot hold or use said items). However, due to random glitches, the check can fail, causing the critical items to be Lost Forever and the rest of the level unwinnable since the crew can no longer progress.
There's a rather inexplicable case of bad design in the game Nancy Drew: Secret of the Scarlet Hand: At one point an NPC gives you a phone number which you have to call later. Normally such phone numbers can be seen later either in the chat box when making a call or in Nancy's journal... except for this particular one, for some inexplicable reason. If you don't (physically) write down the number (and you don't have photographic memory for numbers), it will be Lost Forever. The game cannot advance without that number, and the only option is to look it up from a walkthrough.
If you make it to the top of the tower in Azure Dreams a second time, the only way out is a Wind Crystal. You could be stuck there forever if you're unlucky enough to never encounter a Wind Crystal or have the last one you'll ever see stolen by a Picket.
BioForge: Drain the sweet, sweet alien battery you got from the first alien leader too much (either by healing or firing your arm cannon), and you will not have enough power to charge up your escape vehicle.
In Dynasty Warriors 7: Empires, using the Rock Slide tactic can block a path from enemies and allies alike. However, it can also block supply lines which you need to win. Thus using this ability too many times can block supply routes entirely. If you on the defending side, you'll have to wait for the clock to run out to win. But if you're on the invading side, however...
In Messiah, on the Conveyor level, you enter a room in order to access a platforming section of conveyor belts. If you turn around and leave the room instead, the door will become locked from the inside and you cannot re-enter.
At one point on the rooftop level, you're supposed to have Bob crawl into a air vent and get into a control room; a part of the vent collapses under Bob's weight as he enters. However, you can instead possess a cop who is standing next to the vent entrance, shoot away the glass that surrounds the control room (it's visible below you), then jump down there. But if you do so, you're stuck, as normally your way back would be through a collapsed part of the vent.
In Dark Souls, you meet an NPC in the New Londo Ruins called Ingward. Once you obtain the Lordvessel, he gives you the key that allows you to drain the lower section of New Londo, allowing you access to the Four Kings boss fight. Killing him causes him to drop the key, and is often used for Sequence Breaking. However, a rare bug causes him to not drop the key when killed.
Persona3: the second boss battle can easily put the game into an unwinnable state. The player has no control over the protagonist for the entirety of the day of the fight, which is not known beforehand, and the last chance to save is the night before — and since a boss battle is imminent, saving seems a smart move. Before the battle begins, you're treated to multiple cutscenes and a brief fetch quest, then warped to the dungeon, sans your party members. After battling your way to meet them, you'll be treated to yet another cutscene before the main battle. Even if you've conserved all your magic points and healing items for the main boss (assuming, of course, that you knew it was coming and weren't sidetracked by the battles to your party members), you're still facing two enemies that can constantly change their weaknesses and strengths. Oh, and you need to equip a different weapon — the weakest weapon, in fact — in order to give your party a full spread for physical attacks. As a bonus, only two of your party members are capable of healing spells, including you, and since you're using turn-based tactics, anyone knocked down by the enemy wastes a turn climbing to their feet... only to be knocked down again by the next enemy strike. (Whether or not they fall unconscious depends on whether or not you choose to heal them.) It's an annoying but not difficult battle, but your non-standard lack of control on the day of events makes it possible to put yourself in a situation in which you're under-equipped and under-prepared but unable to fix the problems. Given the expected player level, you also don't have the items you need yet — some healing items work outside of battle, some only work within, but you don't yet have access to the options that restore more than a handful of hit points. You can try consulting a strategy guide, but if you still can't win and your last save takes you back to the day of the battle (again with the goddamn cutscenes), you can either Rage Quit or start over. You need a save at least two days in advance of the battle if you've tried and failed.
In Deadly Premonition if you happen to replay a previous chapter before you finish the game(common with those who want to complete Emily's sidequests, which require specific circumstances to access) and you complete it(save points are disabled during replays, so you have to finish a chapter to save it), it can cause items you need to progress to disappear, like the key to the diner in chapter 9(it can also happen in chapter 23), once it's gone there's no way to progress through the story any further or get the key back without restarting your game. Fortunately that's fairly early in the game, so it won't take long to get to that point again, but it is infuriating if you've been doing sidequests and collecting trading cards
the white chamber has the protagonist gathering body parts one at a time in order to reassemble a dismembered corpse. One of those parts only appears during one of the game's nightmare-hallucination sequences, and it's possible to just walk out of the room without picking it up, which takes you back into the "real" world, never to return. It's especially frustrating because the protagonist is actually standing over it, and the player isn't likely to see it at all: she breaks open a pipeline, causing her to put her back to the camera, and comments that an arm came out. It's easy to assume that she just picked it up herself and go on about your merry way.
In the video game Chuck Rock, there is a gameplay design choice that once a rock is moved, it will stay where it last was. This can create a problem at the beginning of the final level right before the final boss. As you start walking, you see there is a rock close to a tall platform and on top is a green dinosaur. You throw a rock on the platform to kill it, causing it to transform into a devil and attack, but luckily you have enough time to react to this and you retreat, giving enough time to kill it. After this though... you're as good as screwed. The player can't walk around said platform as it is too high for your normal jump, Chuck can't climb, you can't nudge the rock back down, there are no other rocks to use, and seeing as you don't collect power-ups that rules out the possibility of jumping higher. If the player leaves the screen and comes back, the rock doesn't reset. On top of that, enemies don't respawn so the player can't kill themselves, and there's no time limit either so the player is stuck there, without any choice other than reset the game. Hope you remembered to write down the password...
In the Hell's Kitchen: The Game version for Nintendo DS, you can't get the 100% in the weeks two and three, making the game unwinnable by the lack of tests during his development.
beatmania IIDX 9th Style. The game itself is already buggy, but if the song "General Relativity" is played as the first song after a machine bootup, all note judgements no matter your timing will be POORs, thereby making clearing the chart impossible.Explanation The song uses the timing windows of the last song that was played on the machine. Since playing it as the first song after bootup means no song was played beforehand, the timing windows will fail due to lack of timing data.
The Charlies Angels video game contains a Game-Breaking Bug in the ship level that traps the player in a loop, booting them back to the start of the level when you complete it.
Indie game Legionwood can be rendered unwinnable due to how area transitions work on the overworld map. If a tile that transports you to a new location happens to be right on the shoreline of one of the continents, you can accidentally enter it with your ship, and then be unable to access your ship again as it'll be blocked by said tile.
There are several points in Mass Effect 3 that are unwinnable if you're only carrying the Acolyte pistol (or a number of other weapons available during a New Game+). For example, during the mission on Mars, the player character is forced to shoot with whatever pistol they have equipped at an enemy who is charging at them in slow motion. Slow-firing pistols or ones with non-standard properties may not be able to kill the enemy in time, resulting in automatic death.
The hack Hammer Brother Demo 3 is unwinnable because the maker used the wrong blocks in the final arena, meaning the boss (an edited SMB 3 style Bowser sprite) can't break them and the player can't use the screen exit/teleport underneath to reach the next phase of the fight. Of course, given the game's notoriously poor level of quality, this is just the least of its issues.
The other notoriously terrible hack Super Mario Superstar 1 has a final boss which does absolutely nothing. Doesn't move, doesn't attack, doesn't take damage, can't die... This obviously makes it completely impossible to win or see the ending.
In the third dungeon of Byteria Saga: Heroine Iysayana the heroes have to find a unique item, then run into enemy soldiers when leaving the room. Casting an Exit spell immediately after opening the chest would leave you unable to trigger the cutscene and continue. Later versions fixed this by temporarily disabling the spell.
In Darksiders II (all versions) there's a bug where one of several energy barriers in certain levels don't open even though they should, making the level and thus the entire game non-completable. (Incidentally, it seems to be a kind of Disaster Dominoes of causality. Apparently it happens after having been playing for several hours contiguously, and the reason is that, perhaps due to some overflow or leak, in certain cutscenes a sound fails to play, which in turn causes the cutscene to fail to complete properly, which in turn skips a trigger that would have opened the barrier, and this trigger never happens again because the game assumes it can't be skipped in any circumstance.) In most cases if the player immediately quits and reloads, the game will revert to an autosave from before the cutscene. However, many players, not knowing this, have wandered away and caused the autosave to be overwritten by new ones, after which the trigger that opens the barrier becomes essentially Lost Forever, rendering the game unwinnable. The only option is to restart the game from the beginning. (As of writing this, there is still no patch to fix this bug.)
Star Trek Online, Featured Episode "A Step Between Stars". Early in the mission there's a point at which the captain of Tuvok's ship is supposed to get killed by the Voth. If you manage to save him, you break the mission progression.
In The Last Story, if you initiate a sidequest like the Kraken quest and you're not powerful enough to beat it, you're screwed. There's no way to reset a quest either, so you have to start the game over from the beginning.
Rex Nebular and the Cosmic Gender Bender had a well known bug: depending on difficulty level, the game would discourage or prohibit the player from flooding the city unless all necessary items had been collected from the city. The problem: it was possible to collect a repair item and use it for its intended purpose, whereupon it vanished. The player then couldn't proceed because they didn't have the item, even though it was no longer needed.
In the NES game Saint Seiya Ougon Densetsu the player can make the Final Boss unwinnable without realizing. The final boss is fought with two characters (Seiya and Ikki), and the player must use the "Talk" command on him with Ikki before Ikki is defeated. Failing to do that, the final boss will be invincible and no attack from the (resurrected) Seiya will ever do damage to him, eventually leading to his death and a game over.
The game, as it's an adaptation of a manga/anime series, allows the player the choice of doing the battles in the same order that happens officially. However, one can go outside canon and beat the second-to-last boss Aphrodite with Seiya...which leads to him dying and Shun being the only choice left to cross the Path of Roses (which constantly drains his life). However, the exit at the end of this area (Seiya's mentor) only appears for Seiya, leaving Shun unable to continue until his life drops to 0. Oops.
The NES game, Who Framed Roger Rabbit, includes a portion where the player is told to find Jessica Rabbit's phone number, and call her. Even after finding the number, it's impossible to call her from any of the phones within the game. However, if you called that number from a real phone, a recording of Jessica would give you clues on how to continue. Unfortunately, the number now connects to a sex chat line, leaving any players of the game unable to finish.
An early mission of Front Mission has Driscoll hanging around outside the main battle area in his ridiculously overpowered wanzer. Normally he just leaves when you rout all the other enemies and you win. However if you make the mistake of attacking him (which is quite easy thanks to the game's dodgy targeting controls), he'll start coming after you. Once this happens you have no choice but to either fail the mission or reset; he won't stop until all your units are toast and all you can manage back is Scratch Damage.
Batman: Arkham Origins has a very nasty glitch: there are sewers beneath the GCPD that you can reach by taking an elevator. You can simply jump off the elevator and glide into the sewers, but you need the elevator to get back out of the sewer. If you glide off the elevator there is no way to get the elevator to come down so that you can take it back out of the sewers. If you have beaten the game you can still play the game on New Game Plus, but the story mode in which you encounter this glitch is effectively rendered unplayable because you're trapped in the sewer forever.
In Legend of Mana during the Heaven's Gate event, there are two battle arenas that just barely overlap. If you trigger the 2nd one while the first is still active, the game will lock up.
In Dawn of Mana, one in a very rare while in Chapter 4-3, the enemy needed to give you a special key will not move. If this enemy doesn't come to life, you can't kill him to get the key, thus you can't progress.
In Animal Crossing: New Leaf, bamboo shoots planted in the ground will grow and spread uncontrollably if the player doesn't regularly play. If the town is neglected for long enough, it can block you from being able to go anywhere but your house. Players that are unlucky enough to be there without an axe and shovel are stuck there and have to start an entirely new town.
If you choose to take the subway car back to Battery Park just after reaching Hell's Kitchen, you'll get stuck in a permanent loop where entering the subway back to Hell's Kitchen results in the player being transported to the starting point of Battery Park, ad infinitum. The only way to fix it is to reload a saved game from before the glitch was triggered.
After clearing out Battery Park, you're supposed to find the Ambrosia canister. If you leave the zone or dawdle around, Anna Navarre will come to you to inform you she found it instead and tell you to proceed to Hell's Kitchen. If this happens when you're in a corner or dead end of a narrow corridor, you can get stuck forever as she will never back up to let you pass through.
There's an inadvertent bug that can trigger in some playthroughs, where Bob Page simply doesn't appear after you've uplinked Milnet and Daedalus/Icarus have merged into Helios. Unlike the previous example, reloading a saved game doesn't help - you'll have to start a new playthrough over. Luckily, this bug was fixed in the Shifter mod.
Waxworks is chock-full of them, often getting you stuck in the game long after you made a mistake such as feeding the dog without lacing the food with narcotics beforehand, not killing the crocodile at the first (and only) chance you get, lowering a stone pillar from the wrong angle, stranding you in the half of the pyramid that doesn't have the item needed to open the way to the other half, not replacing the screw on the gasoline can preventing you from filling up the drill to give the demolitionist...the list just goes on and on.
In the Calling All Mixels app, sometimes Major Nixel freezes in midair during his jump attack and stays stuck, with no way to reach him to attack him. This makes the level impossible to beat, forcing the player to restart it.
In cult-classic adventure game DreamWeb, during your first mission to kill David Crane, it's possible to get into his hotel without having found a firearm or even starting the series of events to get it ( you need to locate your stoner friend Louis's address by reading a particular data cartridge that's very easy to miss). The game won't stop you from getting two screens away from Crane. Without the Gun, though, you can't get past his security guards, and if you've gotten there, the elevator will no longer go back down because you cut the wires on the control panel to stop it from moving and you may have even already entered the room, which you can't leave without getting shot. If you don't have a save prior to the elevator sabotage, you can't get out of the hotel and get the gun. Most of the game is designed explicitly to prevent this sort of situation, oddly enough.
Monster Hunter: If you go on a capture quest and run out of tranquilisers, the quest doesn't automatically end in failure, but it may as well do.
While playing through first game's Secret Armory of General Knoxx DLC campaign, you eventually confront and defeat the titular Big Bad, and his defeat allows access to the nearby Armory. The hallway you enter is set up to look very secure - you make your way down a hallway towards a glass elevator as heavy doors close behind you with a loud slam. As you enter the elevator, you can see rooms on multiple floors packed to the brim with loot chests of the highest quality. You're meant to push the only button in the elevator, descend into the Armory, and snatch and grab as much loot as possible while a timer counts down. However, the encounter with Knoxx along with the long slog you had to run through to reach him from the closest fast travel station usually left you with a full inventory. If you walked into the Armory's hallway, proceeded to the elevator, and chose to return to town to sell gear, you'd find that you couldn't leave through the entrance you just came from, due to the heavy security doors. If you then decided to Save and Quit, intending to restart in town and sell your Vendor Trash, you could never access the Armory again on your single-player campaign. Many a player 'ported back to town upon seeing the ridiculous amount of loot that they couldn't possibly carry, and made the long trek back to the Boss Fight while avoiding loot, bypassing trash mobs and defeating Knoxx again, only to find that the door to the Armory sealed indefinitely. The game only re-opens the doors to the Armory for future quests after you've looted it in the first place - this willnottrigger if you don't enter the Armory proper! While you could join an online game and enter the Armory if the host happened to be running through any of the associated quests - which would actually give you a quest complete, allowing you to move on to the extra missions - there was no way to progress past this point in a single player campaign where you'd locked yourself out.
The Wilhelm Boss Fight in Borderlands 2 takes place in an area enclosed on three sides by ice cliffs and a sheer drop on the remaining side. While Wilhelm himself cannot fall off, killing him too close to the edge can result in the power core taking a dive, forcing you to exit the game and then reenter it to fight Wilhelm again. Ironically, the power core turns out to be a trap laid by Handsome Jack. Failure Is the Only Option indeed.
In Yu-Gi-Oh! Capsule Monster Coliseum, it's possible, in a match, to end up with pieces that can only move in certain patterns against one that manages to evade them perfectly no matter how hard you try to box it in, and since the A.I. doesn't know when to quit, they'll happily continue to avoid your pieces with it, despite being unable to do anything else. In such cases, the only way to end the match would be to surrender or let the AI destroy your Symbol.
If you play NullpoMino with one of the "Nintendo" rulesets, don't pick modes with a win condition that require you to play at speeds exceeding 1Gnote 20 grid cells per frame, where 1 frame = 1/60 second. For reference, a standard Tetris playfield is 20-22 cells tall. such as any Grade Mania mode. Since the Nintendo rulesets do not have the lock delay necessary to play at higher fall speeds, unlike the "Standard" and "Classic" rulesets, you'll find yourself in a situation just like Level 29 in NES Tetris, i.e. you can't move pieces all the way to the left or the right, preventing you from making lines. It gets worse if the mode starts in 20G (i.e. instant-fall speed), such as any Speed Mania mode, in which case you'll be unable to do anything at all as your pieces helplessly stack to the top for a quick Game Over.
Far Cry will sometimes autosave in the middle of combat. If you were in a position where you could not win the fight, then your only option is to reload an earlier save.
Crypt Of The Necrodancer occasionally creates a "trap" that consists of a valuable item surrounded by four arrow pads. Once you pick up the item, one of the four arrow pads will push you back should you try to leave the square, unless you destroy some of them or have an item that protects you from traps such as the Boots of Levitation or the Heavy Boots. Normally, this wouldn't count as unwinnable, since once the current stage's background music ends, you are forced onto the next level, so you can just wait. However, if you play as Bard, all rhythm-related elements of the game are removed, including the time limit, so if you get trapped between the arrow pads, you have no choice but to quit the game.
StarCraft II: Legacy of the Void unbelievably has this in That One Level, Templar's Return, part 2. Accidentally kill off too many of the enemy's mechanical units? You're screwed, there's no way to proceed. Thankfully, the game was merciful enough to autosave for you right before the start of that part of the level.
AKIRA for Amiga is Nintendo Hard to the max, but stage 4 is literally impossible due to one of the moving platforms being placed too far away to reach.
The Wiki Game - Because the interface does not accept all Wikipedia templates, etc, sometimes you can find yourself on a page which is a Dead End Room with no links to click.
In Ori And The Blind Forest, there's a part in Sorrow Pass where you have to use boulders to block death lasers. A glitch may cause one of the boulders to disappear upon reloading or backtracking, or you can get one stuck in the wrong place, leaving you unable to progress in both cases.