Ah, Sierra. During the heyday of point-and-click adventure games, Sierra was one of the leading names alongside the likes of LucasArts. What truly set them apart was less their stories and quirky humor, which were rather generic in some ways, but their apparent joy in murdering their own pixellated heroes in as many ways as possible. The true enemy for the player and their avatar was less the antagonist and more the developers themselves.
Zarf'snote Andrew Plotkin's Cruelty Scale of Interactive Fiction, as lifted (and revised) from here, here and here, divides video game types as follows:
Merciful: You only ever need one save file, and use that only if you want to turn the computer off and go to sleep. You never need to restore to an earlier game, because there's no way it ever becomes unwinnable.
Say that there is a large button on the wall, with a sign above it that says 'Inorganic Vaporizer Ray'. When you try to push it, the game won't let you. Instead it says something like 'You'd better not. You'd lose that nifty pocket screwdriver'.
Polite: You only need one save game, but if you do something fatally wrong, you won't be given a chance to overwrite it.
The same as Tough, only there's no sign. You will only find out what the button does upon pressing it and noticing that your inventory is now gone.
Cruel: There is no immediate indication that your game has become unwinnable. You think "I should have kept the save I overwrote three hours ago. Now I'll have to start over."
The same as Nasty, only you just hear a humming noise when you push the button, and there are two buttons beside it that do other, plot-important things. Then, a while later, you need to solve a puzzle and check your inventory... "Hey, where's all my stuff?"
At one point in King's Quest VI, Alexander is thrown into a labyrinth and has to find his way out again. This requires certain inventory items, and it's possible to enter the labyrinth without them. If you do, then you can never escape. Better yet, there's no indication of which items you need until you've already entered the maze; anybody who didn't use a guide was banking on pure luck to avoid a restart there.
The game is a bit merciful in this regard. If you don't have the required items when this particular point arrives, then you'll be given time "to prepare", at which point you head back, hopeful that you have everything. If you have everything you need, then you'll simply be taken directly to the labyrinth. But you only get one chance to prepare, and you are never told what preparations you need.
Another example from VI: Alexander's gambit to rescue Cassima involves getting Jollo to switch Shamir's lamp with a fake. To do this, Alexander needs to visit a lamp trader in town and exchange an old lamp he finds in the labyrinth for the exact replica of Shamir's lamp. How do you tell which is the replica? By watching a cutscene. And once you trade the lamps, the trader leaves the game permanently, so if you pick the wrong lamp, you won't be able to pull off the plan, and the game is no longer winnable.
In Quest for Glory II, dropping important items like the mirror and magic lamp would get you stuck later. The latter triggers a unique Easter Egg death.
So does dropping the spare clothes when you go to Raseir. Let's just say the Hero looks good in a veil.
If you're a fighter, you can drop your shield at any point in the game (and although the game never advises you to do so, some people prefer to fight without a shield). If you don't have a shield, you can't fight Khaveen at the very end of the game. If your fighter doesn't have sufficient magic or thieving skills, and you've dropped your shield, the game is unwinnable.
In Laura Bow 2, if you've done everything you could to outrun the murderer in Act 5, but forgot to pick up the boot before or during the chase, you've officially ran yourself into a brick wall and might as well restart because later on you will be trapped in a furnace room unable to backtrack, and you need to give the boot to Steve or else he'll step on a piece of coal and be unable to help you to move the slab hiding a secret passage to go on. This is especially annoying as said boot appears after Yvette dies, but only after you've examined her body and appears in a room you have no other reason to visit until the chase scene, in which case good luck not being freaked out enough to stop and grab it. It was so bad that some versions of the game fixed this by making the boot reappear in the furnace room beside the coal pile if you didn't grab it beforehand.
You'll need the wire cutters before you reach the chase scene in Act 5, because without them you won't be able to cut the wire from the fallen pterodactyl model to bar the door. The wire itself, however, is surprisingly not a case of this (despite the fact every other body besides Ziggy's is unexaminable (for good reason) during the chase scene), as you have time (even without barred doors) to snip the wire if you hadn't already to properly bar the door (although not long).
If you don't have at least a quarter of snake oil left before you take the smelling salts away from the Countess's body, the game will automatically move on and prevent you the chance to refill it before you eventually face a horde of snakes in the secret passage near the furnace. This is especially annoying as while it only takes three quarters of snake oil to move Barney into a position he can be subdued without biting Laura (that is, assuming you start with a full bottle), Laura will only make a comment indicating that Barney is safe to touch after you've used up your snake oil reserves on him. You can easily refill it in the preservation room if you've run out, but there is sometimes a chance where Wolfe will be there (a random chance of such which increases the more you fart around in other rooms), and if he is, he'll kick you out indefinitely and prevent you from getting said refill.
And just to rub it in, the final act subverts the usual Amateur Sleuth antics by making you back up your claims with evidence. What, you forgot to find that mastodon hair on the guy covered in alcohol, or cop a feel of the murdered corpse to pilfer through his pockets? Aw...
Space Quest V had a particularly nasty scenario. At the Genetix segment you are supposed to look to find an important item. If you leave without it, the game will let you know that in bold lettering just after you beam out. note Space Quest V gives you maximum points for doing everything at the first moment that it can be done; if you return for something later, then you can still win. You'll just get fewer points. If you don't pay attention, then much, much later, after having crawled through a complex and stressful series of mazes on the enemy battleship, you confront the Big Bad and realize that you're missing that very item. The Have a Nice Death message then once again tells you what you should have picked up.
Luckily, in AGD's remake of King's Quest 1, you can play a no-dead-ends mode.
In King's Quest III: To Heir Is Human, the game is run on an internal timer. If you aren't in the right place when an event happens, then you're stuck and the game is unwinnable. Usually, there aren't any warnings that there's a time limit for certain things, either... A notable example: after you get the amber stone from the oracle, the pirate ship in the harbor will only be there for twenty more minutes. Then it will leave, forever, taking your only chance to get to Daventry with it. Although if you're desperate, you can always try the random teleporting stone and hope you get lucky and end up there...
That said, you get plenty of time; and once you've finished the pirate ship segment (about two-thirds of the way through the game), the timer becomes irrelevant. (There is one more end-game sequence that's timed — but that's a matter of seconds, not minutes.)
Screw up in making the Dispel Potion in Quest for Glory I (with items like the Magic Acorn, which can be Lost Forever), and the game is unwinnable.
Or if you piss off the Healer by stealing from her. At the time, you are not warned that she'll know what you've done. Did we mention that one of the "hero" classes is the thief?
In King's Quest V: Absence Makes The Heart Go Yonder!, in the area near the pie section (see Cruel), you have to use your rope on an outcropping of rock to ascend it. There are two spots you can choose from. If you pick the wrong outcropping, then it will break and kill you. You cannot retrieve the rope after you've set it in place, and so the game can become unwinnable without warning.
Conquests of the Longbow was fairly merciful; you could screw up so much that you lost the treasure you were supposed to capture or let a major NPC die, and you would still just get a Downer Ending. But on the second day, you're supposed to get a slipper from Marian, who's under attack by a Fens Monk. You can either kill the attacker, at which point she'll give you the slipper as a reward, or let her die and then take the slipper from her corpse. If she died, then you'll die the next day when you go to deliver the slipper.
Also, at one point you can disguise yourself as a jeweler to fleece the Sheriff out of some gold. If you were in the archery contest the day before, the Sheriff's wife will recognize Robin by his distinctive blonde beard. This will get you hanged; you can rub jeweler's rouge on Robin's beard to complete the disguise. If, however, you visit the castle before disguising your beard and then visit it again afterwards, the gate guard will wonder why your beard's changed colour and he'll have you arrested.
Leisure Suit Larry in the Land of the Lounge Lizards is just as easy to mess up in as its sequels, but the penalties aren't as strict and the unwinnable situations are a little easier to see coming. The easiest way to make the game unwinnable is simply by running out of cash and being anywhere but right next to the casino, so you can't pay for cab fare and are basically stuck.
Notably, Galahad asks you to let him die; Gawain says he's beyond help; and Lancelot is, well, indisposed. And they're all saved or left to die in the first half of the game. You get the Grail at the end of the game. Do the math.
In King's Quest II: Romancing The Throne, there is a bridge you must cross (several times) over the chasm, and making just one extra trip across makes the game unwinnable: it will break before you can get the three magic doors opened. This is far from clear.
This gets parodied (and the trope subverted) in Freddy Pharkas, Frontier Pharmacist. There's a rickety bridge, and crossing it generates a message saying something like "Wow, that's pretty unstable. I probably only have three crossings left! I should use them carefully." But in fact, you have to cross it something like seven times, and if you want you can waltz across it all day long. Nothing will happen. (And yes, the warning message is generated every time, which is funny, then annoying, then funny again, and finally annoying.)
Space Quest also has a bridge on Kerona that breaks if you cross it too many times.
In King's Quest IV: The Perils Of Rosella, you can fail to get certain items before night falls, or fail to get a certain item off an island that you can enter only once. If you didn't get them during the day, then you aren't going to get them during the night, and you're stuck as a result. (The magic fruit is the most obvious example, though that gives a Bad Ending rather than an unwinnable situation.) And if you didn't get it off the island the first time, then you don't get a second chance.
The one on the island is worth elaborating on. It's completely hidden; there's no visual cue on-screen to indicate its presence. The only way to find it is to stand in a certain spot and type a simple, but relatively non-intuitive command that has never been used before that point and will never be used again. It's also an object that one would never logically expect to find on a tiny, deserted island.
This particular example suffers from adventure game logic: you've had to go through a lot to get to this island, and the only visible item is something that will get you off the island safely. For no reason other than the fact that you're playing an adventure game, there must be something else on the island. That is quite literally the only reason to search for the particular, hidden item.
King's Quest V: Absence Makes The Heart Go Yonder! has the infamous mountain-climbing sequence, where the player must traverse a treacherous mountain. During the journey, Graham will get hungry, requiring the player to eat and letting the player choose between eating a pie (which can be gotten, and eaten, very early in the game) or a piece of meat (which the player could possibly not have gotten at all). There's also a starving eagle the player meets later on at the mountain, who you have to feed to survive later on in the game. What the game expects you to do is eat a piece of meat yourself, then feed the eagle the rest, and the game never specifies that the meat makes for two servings, as the pie is required later on. Eating the pie, feeding it to the bird or letting the bird starve all make the game unbeatable.
Then there's the time you have to save a rat from a cat. This requires a boot (or a stick, but odds are, you've already used the stick), which is in the middle of the vast, trackless desert, making it very easy to miss. Much later in the game, you are tied up, unable to free yourself or do anything else. There is only one escape: if you saved the rat, then it will eat through the ropes. If you didn't save it, or if you didn't even know it was there...then there's no escape. And even if you did save it, you need another item to escape the room you are in. If you don't have it, the game lets you thrash around for about a minute before abruptly crushing your hopes with a Game Over.
Don't even think about going into the dark forest without the bottle, the amulet, and the honeycomb. Not that you would ever know that you'll need those items... and only those items.
You only have a few moments to retrieve both of the items you need from the temple in the desert, after which you can never go back in. The gold coin is very easy to miss, as it is right next to a larger, more conspicuous bottle. (You are, however, told that you need a gold coin much earlier in the game)
Near the end of this game, you need to capture the wizard's cat to prevent him from telling his master that you're here. If you fail to capture him and he spots you, he says something and leaves; you don't get an immediate game over. You can continue and even save the game, but the game is now unwinnable — the wizard will appear about 15 seconds later and kill you. Save the game after failing to catch the cat? Have fun starting over from scratch. This is in the last part of this game, mind you!
Another Cruel bit near the end: a monster will appear at random and throw you into a dungeon, which you can escape from only once, and only if you remembered to give something to an NPC earlier on. The truly absurd bit is that before leaving, you must inexplicably stick a fishing hook into a hole in the wall and pull out a piece of moldy cheese, which you'll need for another completely illogical task right before the final battle. Forgot to collect the fishing hook 20 minutes ago? Didn't think to fish for cheese in the wall? Too bad, you lose. But at least you can't eat the cheese by mistake. Probably.
If you fail to save Cedric from the harpies, you can continue playing for almost the rest of the game, all the way through Mordack's lair. But Cedric will not be able to fly through the window and save you at the last second.
In King's Quest VI: Heir Today, Gone Tomorrow, you unlock the secret fifth island, the Isle of the Mists after completing the labyrinth. You get precisely one chance to explore the island and if you screw up and don't take the scythe with you before you leave, the next time you return to the island (which may be an hour later), some druids will be waiting for you and will promptly take you off to be executed and you will not have the items required for your escape.
The original Space Quest gave you the chance to sell a hovercraft for money, which you will need. If you refuse, then the would-be buyer will come back and offer to throw in a jetpack as well. If you take his first (jetpack-less) offer then, a few hours of play later, you will find yourself in a situation where you need a jetpack, have no way to get one (or do much of anything besides float in space), and have no idea where you missed the chance to pick one up, Guide Dang It...
Space Quest IV: Unwinnable scenarios return with a vengeance in IV. Forget to write down the time code for SQXII at the start of the game? Well, too bad. In the floppy version (but, mercifully, not the CD remake), the code is randomized — you can't even look it up. Plenty of plot-crucial items can also be Lost Forever. And there are Guide Dang It puzzles again.
For those trying to get 100% completion, there's a truly evil bit with the "Unstable Ordnance". When you pick it up, the game warns you that it's dangerous, but you receive points for it. When you fall into the sewers, it goes boom. So you decide not to pick it up next time, and beat the game. You failed 100% completion. Okay, you then pick it up after you get back out of the sewers instead. You get unavoidably lasered when trying to leave the area by Schroedinger's Enemy (he doesn't show if you didn't pick it up). Okay, try again. You pick it up, then put it back. This yields a profit in points, and accounts for your missing points — but you still get zapped by the same enemy! To get 100% completion, you must pick it up and then put it back before entering the sewers. Every other choice either blocks 100% completion or makes the game unwinnable if you save after it.
Leisure Suit Larry 3 is ridiculous. There is a point where you play Passionate Patti; forgetting even an insignificant piece of attire makes the game unwinnable. (Women have more clothing than you think.)
Leisure Suit Larry Goes Looking for Love (in Several Wrong Places), aka Leisure Suit Larry 2, is even worse: The entire game is strictly linear from start to finish, with several chokepoints where it's impossible to go back to a previous area. As an example: Larry starts the game in L.A., and later moves on to a cruise boat, where he has to escape to a lifeboat before nightfall. To survive the journey on the lifeboat, he needs to have, among other things, a giant soft drink that can only be purchased in L.A. The game needs to be started over if he didn't get one way back whennote To make it worse, you get a one million dollar bill during a certain part of the game. If you go to the convenience store to get the big gulp with the million dollar bill, you will fill it up and stuff it in Hammerspace, but the clerk will tell you that she can't break a one-million dollar bill. You do not have the option of putting the drink back, and any attempt to leave the store will count as shoplifting, resulting in a game over.. The worst, however, is that there are two items that Larry can pick up on the cruise ship (one of them being a bowl of spinach dip) that count towards 100% Completion but must be discarded in the few seconds of interactivity you have before your lifeboat goes adrift, which many players might not even realize exist. (Larry will eat the spinach dip automatically and die of salmonella). And this whole process needs to be repeated several times during the game's other chokepoints.
In the original Leisure Suit Larry, after cutting yourself free from the rope in the honeymoon suite, if you leave the room without taking the rope then the game becomes unwinnable since you can't go back into the room. Unusually for Leisure Suit Larry, the game gives you no warning about this, and it's easy to miss.
Rise Of The Dragon can be Guide Dang It. There are many ways of getting permanently stuck: locking yourself out of your home (although in this one case, there is a way to recover), leaving vital items lying around somewhere (thus losing them forever), picking the wrong dialog option and thus permanently pissing off a vital character (especially your girlfriend — women can be so sensitive...), or letting important events go by unnoticed because you weren't in the right place at the right time. In some cases, the game will inform you when you've screwed up or are about to so you don't hang around wondering what went wrong.
Heart Of China, by the same designer, also suffers from this, with several situations that have very specific solutions.
In the beginning, when you're trying to recruit Chi, you can insult him and have to come back the next day. Fortunately, this only results in the loss of some promised money, and isn't itself unwinnable.
After crashing in the Himalayas, you're given the option of having either Chi or Lucky trudge through the snow looking for help. If you send Chi, the game lets you do everything else right, but he dies before finding help, resulting in a game over. Even worse, if you actually realize that you need to send Lucky, but don't give the healing herbs he has to Chi before leaving, Kate will die and you'll lose five minutes later.
In Space Quest II, near the end of the game, walking into the wrong area releases a xenomorph queen who, if she catches you... kisses you. Deeply, with lots of tongue, and with a large red heart appearing behind you implying she's merely amorous and that this is just a joke scene. The chest burster will kill you quite a bit later, after you defeat the villain and make your escape, but just before you end the game.
It IS possible to finish the game still, but you have a very strict 15 minute timer, which means you can't screw around at all.
Gold Rush can screw you over at any opportunity. Lethal Diseases and deadly bridges asidenote the game will literally screw you over with a variety of "random" events that will kill you, without you being able to do anything about it, to simulate the danger of the cross-country trip, there are several distinct ways to make the game unwinnable:
Sold your house without entering it? You're missing two required items.
Sold your house after looking through your album? Odds are, you missed the family picture you could get, with no prompt, rendering a very late-game puzzle impossible to complete (a later item, only available after a specific time, hints at the photo).
Mistime the departure on the land route? You won't make it. Guaranteed (either your stagecoach gets stuck in the mud early on, or, after several puzzles, you'll be caught in the same snowstorm that almost killed the Donners).
Loseyourmule? Can't reach your brother's shacknote This one deserves special mention: you need to brand your mule, and the only place to do so is in the blacksmith's shop. If you go just a bit too far into the shop, your mule will run off and never be seen again, and the margin between being close enough to the forge to heat your brand and the point where your mule runs off is extremely small.
Most notably, a CIA guard will ask for your ID and give you the wrong one back, even though you're the only one present. If you don't check the ID and notice the mistake immediately, you'll lose much later.
When unexpectedly becoming Captain of a submarine due to an injury, you have to perform duties that real captains leave to their crew. This is doubly annoying because your character wouldn't be expected to know the ship better than its own NCOs. If you don't do them, there will be failures at critical moments.