Examples of Unintentionally Unwinnable in The Elder Scrolls series.
Series-Wide:
- The series has no restrictions on when you can save, so it is possible to save right before an enemy is about to deal a killing blow. If you don't have any other save files with this character, you've effectively blocked any further progress.
Daggerfall:
- 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. However, one potentially game-breaking bug with collision detection can result in the Player Character getting stuck in "the void" after falling through a flight of stairs. This bug has never received a fix.
- Uniquely for the series, a number of quests in Daggerfall are Timed Missions which result in failure if not completed within the time limit. This also includes certain main quest missions. The very first mission in the main quest after escaping Privateer's Hold is such a quest, though there, you at least get several letters pointing you to the quest target before failure. A later quest given by Queen Mother Mynisera involves you tracking down a courier who has a letter. You must wait in a certain city and meet the courier on a certain date. However, the date, as stated in-game, is wrong. If you miss the courier, you fail the quest.
Morrowind:
- Attempting to address the concerns of Daggerfall, Morrowind takes several steps to avert this with its main quest. First, if you kill a main quest important NPC, you receive a pop up message that "the thread of prophecy is severed" which instructs you to reload a previous save. However, it isn't a perfect solution, as some plot important characters do not display this message upon death, and some who are not plot important do. Additionally, Morrowind offers three means to beat the main quest. In addition to the standard way, there is the "backpath" or "backdoor" option. This requires only one living NPC, but it skips the entire story and is pretty well hidden. The third option is to, by whatever means necessary, buff your character so that they can handle the Tools of Kagrenac, Keening and Sunder, without the protective Wraithguard gauntlet. This typically requires exploits or cheats, as the tools will instantly kill any player who isn't constantly regenerating thousands of health points. In all three cases, Keening and Sunder are still required. If you misplace them, you've made the main quest truly unwinnable.
- There's a built-in "backpath" method to beating the main quest to use if an essential character has been killed. It only requires leaving Yagrum Bagarn alive long enough to make you a jury rigged Wraithguard. You can then use it to complete the main quest (though a significantly shortened version) and defeat Dagoth Ur without any other characters needing to be alive. Kill Bagarn and there is no way to actually complete the main quest story (though methods using exploits to defeat Dagoth Ur still exist).
- In one of the quests for the Tribunal Temple, you must convince an old Dunmer lady infected with the Corprus disease to leave Vivec before she infects others. If the player chooses to attack her, they have a small chance of contracting the disease. Unlike the Corprus disease in the main quest, this one cannot be cured by anyone. This breaks the main quest because Dagoth Garus is supposed to curse you with the disease and you need to get it cured by Divayth Fyr.
- If you carry a Dwemer Coherer when talking to Divayth Fyr, he will initiate dialogue for the Corprus cure quest. If you're not at the point where that is relevant yet, congratulations, you've derailed the game. This is unlikely to happen a lot, but if you're the sort of person who carries a lot of clutter and likes to talk to everyone, well...
- A number of sidequests can be made unwinnable (including entire faction questlines) by accidentally selling or misplacing the related item before realizing that it's required for said quest. A list of prominent examples:
- Many items you have to steal during the Thieves' Guild quest line are unique. Worse still, a few are consumable, meaning if you stumble upon them before receiving the quest, it's possible that you already used it.
- The Morag Tong "Threads of the Webspinner" questline is already quite long, difficult, and nearly impossible to complete without a guide. It requires you to find 26 unique, enchanted items scattered around Vvardenvell. Only a handful are on enemy NPCs associated with the questline, meaning that its possible to find them before joining. While each has a unique enchantment, they aren't particularly powerful so it's quite possible to leave them on the dead body of the NPC who possesses it. Dead bodies are cleared from game cells every three in-game days...
- Near the end of the main quest of the Tribunal expansion, you find yourself fighting through (supposed Big Bad) Sotha Sil's Clockwork City. It is populated by his semi-organic Mecha-Mooks, the Fabricants. Each variety, the Verminous and Hulking, drop "elixirs" which share their names. Verminous Fabricants are a dime-a-dozen, and even spawn infinitely at one point if you intentionally keep screwing up a puzzle. They drop Verminous Elixers, which temporarily fortify your Speed. Not bad, but not especially useful. Hulking Fabricants, however, are much less common. Hulking Elixers temporarily fortify your Strength, which is considerably more useful. However, in the Clockwork City's Dome of Udok, you'll encounter a "rusted lever" which requires 100 Strength in order to move, allowing you to advance. If you haven't been building up your Strength attribute (a common issue for Mage-type characters especially), you'll need to use virtually all of your Hulking Fabricant Elixers to surpass that total. (Worse still, if you haven't been picking them up or have already consumed them, you can end up stuck in the Dome of Udok.)
- The enchantments on the Heart of Lorkhan are supposed to be severed with Keening and Sunder, which are specifically scripted for this task, and the Heart is protected from other damage by instantly regenerating health and a large (but finite) health pool. Exploiting the Alchemy system to create a potion that massively buffs your strength or attack, then hitting it with a normal weapon can oneshot it without triggering the endgame scripts, making the game unwinnable.
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.
- There’s a certain dungeon in Oblivion that has a pit with lava and a chest that if one falls into, they will be stuck there. The only way out is to use waterwalking.
- There's a cage in Fort Carmala that contains some rats. The handle to open the cage is right outside it, and you can very easily close the gate and rush in before it actually drops. Seeing as there's no way to open it from the inside, you're now stuck. In the event you're on a console version and you don't have a previous save to load from (you can autosave by waiting), then the entire character is worthless.
- The "Blood of the Divines" quest requires you to sacrifice a Daedric artifact. Fifteen exist in the game, and it is possible to obtain (and potentially lose) fourteen of them before starting this quest, but one of them (the Oghma Infinium) can't be obtained before "Blood of the Divines" is started. This means that players who have lost the first fourteen artifacts still can get hold of an artifact to sacrifice. However, there is nothing stopping an especially insane player from destroying the first fourteen artifacts, obtaining the Oghma Infinium (knowing, by this point, that it is needed for the sacrifice) and destroying it as well, rendering the main questline unwinnable.
- The Water Walking effect also works on lava. This means that you can freely travel across lava. The problem comes in if you're crazy enough to go so far out of the map that you fall off the world and didn't save before hand. Good luck swimming up from the bottom of an ocean of lava.
Skyrim:
- 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.
- It's possible for the player to become trapped in Bloodskal Barrow if they enter the dungeon, then leave it and allow it to reset. Only the original version of the Bloodskal Blade can fire the sword beams necessary to open the door that allows further progress. If the dungeon ever resets without it being collected then it will be replaced with a copy that cannot fire those sword beams and since the player has to drop down a cliff to reach it they can't go back the way they came either.
- Unlike the rest of the series, it was initially possible to quicksave while in mid-air. This means you could jump off of a mountain and quicksave, leading to your inevitable death with each reload. Patches have since disabled quicksaving when you're airborne or on a steep slope.
- If you are fleeing dangerous foes with whom you're in combat, you may flee through a door that's an area boundary but be taking continuous damage from poison; the damage does not stop while you are transitioning areas, and your autosave on the other side may be of a dead character, leaving you endlessly reloading a dead character unless you interrupt the death animation by loading an earlier save.
- There seem to be a number of "prisons" and similar places where you can get permanently locked into with seemingly no way out. One example is in Brinewater Grotto. There are three levers, two of them open and close doors leading to a barred room with some fish inside. By standing close to the gate, pulling the lever and activating the shout Slow Time, you can run in before it shuts. However, there doesn't seem to be any way out, other than loading a save. You can't seem to reach the lever, there's nothing that can kill you to respawn outside, you can't Fast Travel, so you're stuck forever.
- "The Wolf Queen Awakened" quest can only be triggered by leveling up after completing "The Man Who Cried Wolf". Prior to patch 1.9, you could make this quest unobtainable by reaching the max level. Reaching max level requires you to max out all skills. After patch 1.9, you could reset skills and gain more levels, but the problem wasn't quite solved — the game crashes if you have more than 255 unspent perk points, effectively capping your level at 510. The probability of doing this by accident is zero.
- Major NPCs, such as important quest givers, are flagged as essential by the system; if you attack them until they reach zero health, they will simply fall unconscious. But, the "essential" flag doesn't protect them from the insta-kill transformations the Wabbajack staff can inflict. For instance, it may turn them into a sweet roll, which you can then eat.
