History UnintentionallyUnwinnable / SuperMarioBros

* At a certain point in the game, the pipe that leads to Peach's Castle Dungeon becomes accessible by going to a question-marked spot in Peach's Castle. Later in the game the player will have to go back to Peach's Castle via Peach's Castle Dungeon. If the player did not go to the question-marked spot at Peach's Castle beforehand, the player will be stuck in the dungeon, as the pipe that connects to Peach's Castle and the dungeon doesn't appear. This was fixed in the Japanese and European releases.

* In the DS remake, should you jump down to the branch in the trunk where you fight Goomboss, [[CuriosityKills you will be stuck with no way to go back up]], and will have to either fall into the bottomless pit below or go to the pause menu to restart. Then again, it takes a lot of timing and precision to get there, so you would have to purposefully try in order to pull this off.

* In ''VideoGame/SuperMarioGalaxy2'', the second mission of Slimy Spring Galaxy requires you to do a point challenge that starts with a very steep one-way slide, but you get warped back to before it after the time for the challenge runs out. However, you can get yourself stuck if you jump back down the slide AFTER the Star appears.

* During Chapter 2, Mario and his party must escape from the Great Tree before a bomb goes off. Letting the timing run out will result in a NonStandardGameOver. If you save the game with only a few seconds left, you'll end up trapped in a situation where the game over is impossible to avoid, as the timer will run out during a cutscene. If this happens, you'll need to start a new file.

** There's two springs and a Save Block in Mt. Lavalava. If the player jumps on the second spring, then does a well-spaced spin jump to hit the block, they can bring up the save prompt and control Mario at the same time. If the player has 1 HP and saves just as they are about to fall on a Spike Top, Mario will spawn, fall on the Spike Top, and die, causing an infinite death loop.

* The only way to kill a Boo in the game is to jump on it after paying for the full game. Why the requirement to have bought the full game was added is unusual, considering the first proper level with any Boo in it is past the levels you can play for free. The Toad Rally prevents this from being an issue by only allowing you to play in areas that you've beaten, but the Remix 10 mode doesn't have this filter, meaning if you haven't bought the fill game yet and the interior area of world 5-3 "Boohind Lock and Key" is chosen as one of the 10 stages, you're stuck since there's no way to kill the Boo holding the key to open the door. If you were going for a 35-medal run, too bad.

* Being a level-creating game, getting Mario stuck with no way out is prone to happen in ''VideoGame/SuperMarioMaker''. Hence, there is an option to pause the game and start over. (If you're playing someone else's course, Mario loses a life, then returns to the start.)

* During Chapter 2, Mario and his party must escape from a the Great Tree before a bomb goes off. Letting the timing run out will result in a NonStandardGameOver. If you save the game with only a few seconds left, you'll end up trapped in a situation where the game over is impossible to avoid, as the timer will run out during a cutscene. If this happens, you'll need to start a new file.

* It's possible to get stuck in the first fortress of World 7, which requires you to use a Raccoon or Tanooki powerup in order to fly up into the pipe that leads to Boom Boom. While the level is kind enough to provide you with a Tanooki Suit in a bonus room, if you hit the block containing the Tanooki Suit and immediately leave the room without collecting it, the suit will be lost; reentering the room will not respawn it. Should you do this and not already have a flight powerup, the level will be impossible to beat. Your only option will be to either let the timer expire, or commit suicide by jumping in the lava (there are no enemies in the level other than Boom Boom).

* The only way to kill a Boo in the game is to jump on it after paying for the full game. Why the requirement to have bought the full game was added is unusual, considering the first proper level with any Boo in it is past the levels you can play for free. The Toad Rally prevents this from being an issue by only allowing you to play in areas that you've beaten, but the Remix 10 mode doesn't have this filter, meaning if you haven't bought the fill game yer and the interior area of world 5-3 "Boohind Lock and Key" is chosen as one of the 10 stages, you're stuck since there's no way to kill the Boo holding the key to open the door.

* A softlock can happen late in the game due to a GameBreakingBug found in Shangri Spa. To proceed with the story, the player must bathe in four spas and stamp a stamp card for each spa to earn a VIP ticket. If a player receives the ticket, enters the area that requires it, and leaves, the ticket will be removed from their inventory. The game will now think that the player still needs to stamp their stamp card, even though they don't have the card either, and with no way to regain the VIP ticket or stamp card, there's no way to move forward. If you've saved after that, then there's no choice but to delete your file and ''start from the beginning.''

* One level (World 2-2) features two pits, one of which becomes a trap, but only if you're patient enough to dig up all the dirt in it. And unlike most other games in the ''Franchise/SuperMarioBros'' series, there's no [[TimedMission time limit]] to wait out, although there is a [[PressXToDie suicide code]] to restart the level at the cost of a life. This was fixed in the GBA port ''Super Mario Advance'', which added a vase at the bottom of the pit. Entering and leaving the vase causes the dirt blocks to reset, allowing you to escape if you manage to get yourself stuck.

* In some states that have springboards, they may fail to load due to sprite limits. If this happens, touching the space where they should be will get the player stuck until time runs out.

* In World 1-2, players are taught that jumping onto the ceiling and running past the exit takes them to a hidden WarpZone. Any unfortunate player who attempts to do the same in a castle level will find that they cannot run past Bowser - the screen simply stops scrolling there, and the RatchetScrolling prevents them from going back.

* In World 1-2, players are taught that jumping onto the ceiling and running past the exit takes them to a hidden WarpZone. Any unfortunate player who attempts to do the same in a castle level will find that they cannot run past Bowser - the screen simply stops scrolling there, and the RatchetScrolling prevents them from going back.

* A softlock can happen late in the game due to a GameBreakingBug found in Shangri Spa. To proceed with the story, the player must bathe in four spas and stamp a stamp card for each spa to earn a VIP ticket. If a player receives the ticket, enters the area that requires it, and leaves, the ticket will be removed from their inventory. The game will now think that the player still needs to stamp their stamp card, even though they don't have the card either, and with no way to regain the VIP ticket or stamp card, there's no way to move forward. If you've saved after that, then theres no choice but to delete your file and ''start from the beginning.''

** Also happens in the original ''SMB''. If you jump into where the springboard would be, you get stuck until the timer runs out.

* There are some places where you can jump on the ceiling in a castle level (i.e. x-4 level) and get stuck because of the game's RatchetScrolling, and you have to let the timer run out.

* ''Mario 64'' has all the fights against Bowser requiring you to throw him into bombs to hurt him. It's possible to run into the bombs yourself via long jumping, and doing this to every bomb in the arena makes the fight unwinnable. Note that hitting three bombs will do more damage than Mario can survive, requiring the player to [[UnwinnableByInsanity collect coins from the aftermath of Bowser's flames to have enough health to destroy all five.]] The remake for the DS fixed this by always having a bomb respawn in another, random location if the last one was detonated.

* ''Mario 64 has all the fights against Bowser requiring you to throw him into bombs to hurt him. It's possible to run into the bombs yourself via long jumping, and doing this to every bomb in the arena makes the fight unwinnable. The remake for the DS fixed this by always having a bomb respawn in another, random location if the last one was detonated.]]

* The MinusWorld, reachable by performing a glitch in World 1-2. It's Unwinnable because the stage loops back to the start whenever the alleged exit is reached, and Insane because turning the World 4 warp pipe into the World -1 warp pipe is almost impossible to do by accident. Averted in the Famicom Disk System version, whose MinusWorld has different levels. It's actually possible to complete the game this way in the Famicom Disk System version (and it takes less time than doing it the normal way).

* In World 7-5, there's an area where you fall into a room where the way out is a one-square-high gap to slide through (if you're big) or walk through (if you're small). If you enter wearing a Frog Suit and don't keep one of the Bob-ombs to deliberately get hit and therefore get rid of the Frog Suit, you're stuck and have to wait for the timer to hit 0. While this would usually be UnwinnableByInsanity [[ThisLooksLikeAJobForAquaman considering the Frog Suit's purpose and general rarity outside of it]], 7-4 happens to be a water level and the room in 7-5 appears fairly early on, meaning it's not unlikely you'll forget to dispose of the Frog Suit before you enter.