[[quoteright:350:[[VideoGame/PacMan https://static.tvtropes.org/pmwiki/pub/images/splitscreen_1.gif]]]]
[[caption-width-right:350:[[https://www.youtube.com/watch?v=6SqUzR0XOfA Welcome to Level 256.]]]]
->'''Homestar Runner:''' Hey Strong Bad, what's a kill- kill- Kill Screen?\\
'''Strong Bad:''' Oh, that's when you play a video game for ''so'' long, and get a score ''so'' high, and have a life ''so'' depressing, that you break the video game!
-->-- ''VideoGame/StrongBadsCoolGameForAttractivePeople: Episode 5: 8-bit is Enough''

Ah, the iconic games of our youth. We humbly sit at the 256th level of ''VideoGame/PacMan'', proud of our meager ach--''[[SuddenlyShouting WHAT THE HELL HAPPENED TO THE SCREEN?!]]''

Yep, the Kill Screen, enemy of completionists of yore. The result of an EndlessGame being played for such a long time without a GameOver, and the player advancing so far that an internal counter (like the current level number) reaches its inherent limit (often 255 or [[UsefulNotes/PowersOfTwoMinusOne some other similar number]]) and [[OverflowError "overflows"]] (e.g. resetting itself back to zero), causing a GameBreakingBug to result.

This is a common occurrence in older coin-operated video game machines, as the designers once had reasonable expectations that players would not have the time, patience, or quarters necessary to play the game for so long. But they underestimated what obsession can reserve on time, free up on patience and fish out of pockets. In addition, memory usage of making games had to be very efficient, forcing programmers to store level values in more unusual way. This resulted overflown numbers often altering sections of game's memory in a way it caused it to crash. It's less common for players to run into these in later games on stronger hardware with a higher overflow point; while that point ''is'' still there, it's so much higher that players will usually have to do weird things outside the scope of normal gameplay to trigger the Kill Screen.

The results... aren't pretty: ''Pac-Man'', for example, [[GoneHorriblyWrong goes horribly wrong]] as it attempts to load Level 256, causing half of the screen to become filled with unreadable garbage, rendering the level {{Unwinnable}} in the process.

A Kill Screen can apply to anything: be it a sequence, a level, or even a respawn error (though the latter is quite rare).

Most definitely related to and/or cause of UnintentionallyUnwinnable, although the act of merely ''reaching'' the Kill Screen may be considered (in and of itself) a form of victory.

[[http://donhodges.com/how_high_can_you_get2.htm This]] [[http://donhodges.com/how_high_can_you_get.htm site]] explains the Kill Screens for ''Pac-Man'' and ''VideoGame/DonkeyKong'' -- and actually contains patches to fix them.

Compare and contrast MinusWorld, a level that is found by exploiting a glitch and is at least semi-playable, rather than breaking the game outright.

A GlitchEntity is a game sprite that exists because of similar internal bugs. See also MillenniumBug, which people feared would be triggered by a similar overflow issue.
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!!Actual Kill Screens:
* ''VideoGame/PacMan'':
** The Stage 256 error replaces half the maze with random graphics, making it impossible to continue since some of the pellets you must eat are overwritten. Even Website/{{Google}}'s Pac-Man Doodle [[https://www.youtube.com/watch?v=9us4CyGXJpA references it]]. Also the "Forbidden Maze" in ''WesternAnimation/PacManAndTheGhostlyAdventures'' is called 'Maze 256'
** In ''Pac-Man Championship Edition DX'', the 65th fruit item on the right side of the field will affect the right-hand side it is collected on instead of the left-hand side it's supposed to. This can result in pellets being stuck in walls, making it impossible to continue, and if the player is smart (and aware) enough to clean out the side of pellets first, no more fruit spawn. [[https://www.youtube.com/watch?v=v_iYcHsU6k8&t=9m35s Here's an example of the glitch in action.]] This does (in theory) place a cap on the "Half" course that cannot be beaten, but only Free Mode is affected, as the "Half" course is only ranked on Time Attack courses.
** Now an AscendedGlitch in the form of ''Pac-Man 256'', an endless runner where the objective is to get as far as you can while being chased by an AdvancingWallOfDoom in the form of the unreadable garbage from Stage 256.
* Happens in ''VideoGame/DonkeyKong'', in which the overflow sets your [[TimedMission death timer]] to 400[[note]]which is about 4 seconds and is doubtlessly impossible[[/note]]. Very few have gotten there legitimately, as shown in the documentary film ''Film/TheKingOfKong''. Interestingly, the kill screen is right around the point where a very-top-level player can score a million points before reaching it.
** The NES version becomes impossible at ''level 4'' due to a critical design error. [[note]] The mechanic in the arcade version where the springs in the "Spring Stage" can appear at three different positions is not present in the NES version. Because the springs get faster every level, you MUST exploit this in order to beat the level later on, but since it only happens on the arcade version, the NES version hits an unintentional early kill screen.[[/note]]
* As demonstrated in [[https://www.youtube.com/watch?v=aJFXJ1QXyZ0 this video]], once you make the grueling effort to reach the 133rd stage of the NES version of ''VideoGame/DonkeyKongJunior'', the game will start to behave strangely by playing [[SongsInTheKeyOfPanic the "time-running-out" jingle]] throughout the level and the bonus timer will display invalid scores such as "[=E800=]". By the time you reach the 135th stage, DK Jr. and the enemies will never spawn in and the game will hang for a moment before crashing spectacularly, displaying garbage graphics all over the screen, at which point there is nothing else for the player to do but reset the game.
** The arcade version has an actual kill screen where it displays the level number as "F" and Jr. always gets stuck on a platform above the water, eventually dying due to an issue with the time limit similar to the original ''Donkey Kong's'' kill screen. [[note]] It has a time limit of 700, which actually ''is'' possible to beat, at least on the NES version. However, the aforementioned issue of him getting stuck makes it impossible anyway. [[/note]]
* After clearing round 255 of ''VideoGame/DigDug'', you go to round 0, a completely messed-up level with a Pooka starting right on top of Taizo, killing him instantly before he can do anything. (If you clear this level via a cheat, the game loops back to round 1.)
* ''VideoGame/HeroesOfMightAndMagic 3'' had a glitch that would crash any game after the third "month" of play. This was corrected, though.
* ''VideoGame/{{Tetris}}'':
** The original [=NES=] ''Tetris'' becomes nigh impossible at Level 29, at which point the pieces drop too fast to move them into the extreme left and right edges of the screen, which is why later games adopt the "lock delay" mechanic, first seen in Sega's 1988 arcade version of ''Tetris'', that allows a piece to still be moved around when it hits the stack or floor. With the emergence of techniques such as "hypertapping" (pressing the directional button faster than the game's repeat rate) and "rolling" (holding a thumb against the directional button and using multiple fingers on the back of the controller to get an even higher rate of presses) players have become able to survive for longer periods of time at level 29 speeds.
** If a player is superhuman enough to survive past level 29 for around 120 more levels, they hit a point where the score counting code could take longer than a frame to execute, resulting in a true kill screen (described in more detail [[http://meatfighter.com/nintendotetrisai/#The_Kill_Screen here]] and first achieved in regular play at the tail end of 2023).
*** It is theoretically possible to play in a way that deliberately avoids the game crashing (which can happen any level 155 and higher). If level 255 is cleared, then the game would wrap around to level 0 and stabilize again. [[https://docs.google.com/spreadsheets/d/1zAQIo_mnkk0c9e4-hpeDvVxrl9r_HvLSx8V4h4ttmrs/edit?pli=1#gid=1013692687 This painstakingly-researched document]] outlines the possible crashes and workaround in detail. Thus, it is theoretically possible to subvert the kill screen.
** ''Tetris'' prior to the 2001 reform also featured a largely theoretical "kill sequence", whereby the random flow of pieces can include a stream of S- and Z-shaped blocks that cannot be used to create complete lines. Assuming a perfect random number generator (and that the programmers have not spotted the problem), such a sequence is bound to happen in a game that is long enough, though chances are so slim that chances are no one will ever actually encounter it even over billions of normal-length games. The implementation of the "bag" randomiser (in which the game deals groups of 7 pieces that contain one of each type) has removed this possibility.
* In ''VideoGame/RCProAm'', the [[TheComputerIsACheatingBastard cheating yellow truck]] eventually makes the race literally {{unwinnable}}. While you only need to avoid last place, the other trucks will eventually speed up as well.
* In ''VideoGame/DuckHunt'', a kill screen occurs at Level 100 in Game A (1 duck). The level is displayed as "Level 0", ducks fly at insane speeds and jump around the screen so fast they're essentially unshootable, and then the dog repeatedly laughs at you until you get a Game Over- sometimes the duck doesn’t even appear. Interestingly enough, if you accomplish this in Game B (2 ducks) or Game C (clay shooting), it causes everything to become incredibly slow, after which it proceeds normally to level 1. In Game C, you even get to see up-close blast animations that are almost impossible to get at normal speed.
* In ''VideoGame/{{Galaga}}'', clearing 255 stages will yield Stage 0, which crashes or soft-locks the game unless [[NintendoHard the DIP switches are set for the toughest difficulty level]], giving us an example of Kill Screen crossed with accidental EasyModeMockery.
* Many games from the infamous ''VideoGame/Action52'' do this, e.g. Thrusters starts blinking on and off in the second level, Atmos Quake has an invisible death barrier at Level 5, and Star Evil displays a blank gray screen on Level 4. In other versions of this cartridge, some of these levels won't crash. Unlike most examples on this list, Action 52's kill screens are extremely easy to encounter and happen early on, as opposed to the usual convention of a kill screen only showing up so far into a game that 99% of people will never play long enough to see it. The Genesis version was a little better in this regard, though the final game will crash when you complete one level of it.
* ''VideoGame/BubbleBobble Revolution'' was {{unwinnable}} because the boss of Level 30 failed to spawn. Notable in that this was ''not'' an EndlessGame. However, this issue only affects the initial USA release of the game; the European and Japanese versions don't have this issue.[[note]][[Creator/{{Codemasters}} The publisher]] did at least recall the game, releasing a version which fixed the glitch. This version can be distinguished by the code on the cartridge: if the code doesn't have "-1" at the end, you have the glitched version, and if it does, you have the fixed version.[[/note]]
* ''Puzznic'' has a almost certainly intentional kill screen in the arcade version. Once you beat a level 8 section, it goes to the section below it on the level select, with the timer sped up. Each block of 4 levels completed speeds up the timer. After you beat 8 (8-4), it goes back to 8 (1-1) with the timer even faster. If this is the second time you have played 8 (1-1) this game, the timer goes so fast that it's completely impossible to beat the screen a second time.
* In ''VideoGame/{{Minecraft}}'' Beta 1.7.3 and earlier, terrain generation and game control near/outside of ±12,550,820 meters from the mathematical center of the map would completely freak out. As of earlier versions than even Minecraft Alpha, the map size is officially "infinite", but modern computers and Java Virtual Machines can't handle infinity. 12 million on a co-ordinate scale is just a little too high of a number for the virtual machine to handle. The cliffs that generate abruptly past this point are popularly known as "The Far Lands", and are the most well-known feature of this glitch. The terrain turns into strange, borderline ExistentialHorror-looking behemoths that seem to generate a crooked, minced reimagining of normal terrain in a 2D slice, and then the engine stretches that slice like a polygon prism into infinity. People who visit this location notice all kinds of crazy stuff, like stuttery movement, displaced block outline indicators, dropped item entities jittering back and forth, and extreme frame and responsiveness lag. It is technically possible to walk there in survival mode, and some people are currently trying, but it takes years to do it without cheating, so most people just hack the game and teleport there to get screenshots. Notch was going to fix the glitch, but then decided that it was cool looking and kept it in. In September 2011 the Beta 1.8 patch replaced the entire generator with a new fractal based one which unintentionally killed off the cliffs, and socially, the Far Lands title, which the fandom no longer uses in further versions. It did not, however, fix computer science's inherent problem with trying to parse infinity. In versions between Beta 1.8 and Full Release 1.7, the iconic cliffs are gone but many of the glitches were still present, including fake chunks and session crashes, and possibly a few new ones like bloated models for placed redstone and tripwires. Obscurely, this new location is known as The World Boundary, which became significantly less interesting once it was truncated entirely by the world border in Minecraft Full Release 1.8.
* ''VideoGame/{{Rymdkapsel}}''[='=]s {{endless|Game}} enemy waves get more powerful with each successive one, and also spawn faster. Eventually, you hit a point where as soon as the wave timer starts to fill up, the "incoming wave" siren plays. At this point, it is impossible to do ''anything'' besides have all your minions on defense stations, lest you get destroyed even faster.
* The early Creator/{{SNK}} arcade game ''Sasuke vs. Commander'' freezes right as you begin to enter the [[BonusStage Magic Bonus]] of Round 17.
* ''Learn to Fly 3'' has this when you reach an altitude/distance of 107,375,182 units, due to that being the maximum possible value for any position in Flash. If you reach that cap vertically, the results are relatively mundane; either you [[http://i.imgur.com/ninCdP6.png?2 freeze in place]](if your shuttle was oriented straight up when you hit the cap), or you [[http://i.imgur.com/ubBjgRH.png?1 start going sideways]](if your shuttle was tilted in either direction when you hit the cap). Either way, unless you steer(which will cause you to start going sideways if you froze when you hit the cap), you won't lose any more fuel--you could keep going indefinitely unless you used up all of your fuel via steering or aborted the launch yourself. If you reached the cap horizontally, however, the results are far more interesting; you're treated to [[http://i.imgur.com/u1tzmEM.png?1 the sky trying to be the ground]] before the game locks up and forces you to refresh.
* ''Pango'', a DOS ''VideoGame/{{Pengo}}'' clone, crashes on level 49 due to a divide by zero error.
* In ''VideoGame/BurgerTime'', Level 28 is considered the killscreen. The baddies explode into manic hyperactivity, and if you survive for a nearly-impossible [[https://www.youtube.com/watch?v=o37PR-D9PQ0 90 seconds]], then freeze into agonising slow motion. The fast food you need to drop ''also'' goes paralytic. The stages are still beatable, but good luck watching food fall for hours per stage!
* Wave 256 on ''VideoGame/MissileCommand'' goes back to the original slow speed, meaning it will take a long time to actually complete the level. If you do manage to beat it, you will warp back to level 1. Despite saying 0x score on the level start, you will actually earn 256x points, so you can earn millions of points. Meaning, yes, this is an early example of PinballScoring in VideoGames.
* ''[[VideoGame/BuzzyTheKnowledgeBug Let's Explore the Airport with Buzzy the Knowledge Bug]]'' has a developer-induced kill screen in the "Time To Play" activity "Lost Luggage", a real-time puzzle game where players must manipulate conveyor belts and other contraptions to guide luggages into like-colored bins. Upon reaching the 99th and final level, the player will discover that it is impossible to complete [[LuckBasedMission without a huge stroke of luck]], since the only way to bring a luggage to a bin is to drop it into a huge network of chutes, in which the exit is completely randomized, and will likely lead it into a bin of the wrong color, causing the level to restart. Since the developers [[NoEnding never bothered to put in something at the end of the level]] [[AWinnerIsYou to congratulate the player]], the only thing that'll happen if they do beat it is to get sent back to level 1.
* ''VideoGame/ArkandianLegends'': Floor 26 of the Mystery Dungeon in ''Revenant'' is a glitchy screen which flashes a bunch of the game's items, making it impossible to progress. Though refreshing the game to escape isn't necessary, only heading out of there is enough.
* ''VideoGame/CallOfDutyZombies'':
** The Treyarch-produced ''VideoGame/CallOfDutyZombies'' games happen to feature one of these. Zombies begin each game with 150 health, and this increases each round by 100 until round 9, at which point health is multiplied by 1.1 for every subsequent round. The game records this health value using 32-bit binary, which will reach its limit of 2,147,483,648 on round 163. The game, however, treats the first digit of that binary as a sign bit. As a result, Zombies on Round 163 have health in the negative, which depending on the game means they will either default to just 150 health (''World at War'' and ''Black Ops'') or die the instant they take damage (''Black Ops II''). As the binary continues to count, this continues to be the case of every odd-numbered round until 185, at which point the 1.1x multiplier falls out-of-sync, and the glitched rounds become more sporadic. This phenomenon has been dubbed "Insta-Kill Rounds" by fans, and is considered a GoodBadBug for giving players an unintentional set of [[BreatherLevel Breather Levels]] at that point in a game.
** Maps in certain ''Call of Duty'' games are also prone to a phenomenon known as "Reset"; if you stay on a map for long enough, the game will boot you to a loading screen and restart the level from scratch. This is a failsafe that is triggered if the game's entity accumulator reaches a certain point, which because the game is always creating entities will happen eventually. During regular gameplay this is near-impossible to witness, as it can take dozens or even hundreds of hours to reach the limit depending on the map. It is most relevant to hardcore ''Zombies'' players, as the Reset puts a hard limit on how long you can play a map for, and thus how many rounds you can reach. The exact time can vary between games, but on most ''Zombies'' maps the Reset occurs at some point around 75 hours, meaning at the very highest level competitive ''Zombies'' players have the objective of seeing how many rounds they can reach in that time.
* In 2K’s MLB video games, if a team scores 256 runs, then the game will automatically end. Granted, to do this you pretty much have to be trying to get that many runs in the first place.
* In the ZX Spectrum and Amstrad CPC ports of ''VideoGame/{{Gladiator}} (Great Gurianos)'', the developers ran out of memory to program the ending, so they [[UnwinnableByDesign intentionally made the final opponent unbeatable]].
* ''VideoGame/{{Dogyuun}}'' is supposed to loop indefinitely as with most Creator/{{Toaplan}} games, but the game always crash shortly after entering loop 5. According to an interview, the developers did not find this glitch because nobody on the development team was good enough to get that far.
* ''VideoGame/{{Bosconian}}'' is, like most Namco games, meant to loop after awhile with top speed. However, [[https://youtu.be/DxcB9TyxOmc?t=13469 on Round 0]], the game throws a version of Round 1 with the calculation for the ship's speed broken--namely, the acceleration of the player ship no longer capped, so the player will eventually begin hopelessly careening at rapid speeds (undoubtedly towards an obstacle). Notably, the player ''can'' actually beat this stage if they have a high enough stockpile of lives (and seeing as how, on the default DIP switch settings, the only limit to lives the player can obtain is tied to the score they obtain, this is very much possible) and promptly kamikaze themselves into the stations. Should the player best that, the game will loop back to Round 2 (counted as Round 1) with the base speed as though nothing happened.
* Endless mode in ''VideoGame/DanceDanceRevolution 2nd MIX'' will function normally up to stage 255. On stage 256, the stage counter will go from displaying an ordinal stage number to displaying "Min Stage", but otherwise the game will still function normally. Also, while the game normally provides a break every 5 stages (so one is provided after stage 255), another break is provided after stage 256 [[note]]Possibly due to 256 rolling over to 0, and 0 being interpreted as divisible by 5[[/note]]. On stage 257, however, the screen will be blank white (albeit the music is still playing). [[https://www.youtube.com/watch?v=yQKMcEKX7YY Source]]
* Windows 95 and 98 will do this. After 49.7 days of up time a millisecond counter will overflow and crash the [=OSes=].
* In the [[ObviousBeta rushed]] [[PortingDisaster Commodore 64 port]] of ''VideoGame/RoboCop'', Level 3's time limit makes it impossible to complete without glitching through walls, which was likely intended to prevent players from accessing the unfinished Level 4.
* Due to the limitations of the engine it runs on, ''VideoGame/{{Balatro}}'' has a kill screen on reaching Ante 39, where the required chips in order to beat the Small Blind is so massive that it causes an overflow error which is given as [=NANeINF=] as the score required. And even if you have a build that can score [=NANeINF=] chips, it still counts as ''less than the chips required to win'', thereby ending the run.

!!Parodies, references, and Lampshade Hangings:
* In Episode 5 of ''VideoGame/StrongBadsCoolGameForAttractivePeople'', one puzzle involves ''deliberately'' triggering the Kill Screen in "Gel-arshie's Pro Fruit-Boarder". The reward is Gel-arshie himself as a party member. The solution is [[spoiler:to increase Professor Pineapple’s fire rate to maximum, then swap the bins containing damaging fruit and scoring fruit.]]
* ''VideoGame/BioShock2'''s DLC ''Minerva's Den'' has a mini-game called Spitfire. If you get the highest score, you get a "kill screen" that shows all the sprites, some large numbers, [[spoiler:a large R]] and [[spoiler:a golf club]].
* The back cover of ''[[ComicBook/ScottPilgrim Scott Pilgrim vs. the Universe]]'' has a picture of 8-bit Scott opening a door to Subspace, which apparently looks like a Kill Screen: it and the open doorway is filled with garbled sprites and text.
** In the tie-in video game, Subspace deliberately contains random garbled shapes and text.
* In an episode of ''Series/{{Chuck}}'', the nerd must get the secret codes to a Cold War satellite by getting the Kill Screen in ''VideoGame/MissileCommand''.
* The webcomic ''2P Start'' referenced the ''Pac-Man'' kill screen in [[http://www.2pstart.com/2009/08/05/the-end-of-the-end/ one comic.]]
* The high-brow gaming magazine ''[[http://www.killscreenmagazine.com/ Tom Clancy's "Kill Screen"]]'' is named after this.
* In ''Fanfic/WhiteDevilOfTheMoon'', Nanoha, playing on the Sailor V arcade game the Sailor Senshi use to train, manages to get 999,999 points on her first try, resulting in the game suddenly ending and her getting extra prizes.
* ''Series/{{NCIS}}'' had an episode built around the Kill Screen as a theme. [[spoiler:The VictimOfTheWeek had encoded vital information into it.]]
* On an episode of ''WesternAnimation/TheVentureBrothers'', Henchman 21 despairs at having seen everything life has to offer. He lists "the Donkey Kong kill screen" alongside "[[Film/BladeRunner attack ships on fire off the shoulder of Orion]]".
* Parodied in ''Filibuster Cartoons'' [[http://www.filibustercartoons.com/index.php/2012/06/06/endless-jubilees-2/ here]].
* The [[TheStinger Stinger]] LogoJoke to ''WesternAnimation/WreckItRalph'' features half the Walt Disney Pictures logo getting changed into the ''Pac-Man'' kill screen.
* As WesternAnimation/DangerMouse is playing "Space Invaders" on his videophone (episode "Tiptoe Through The Penfolds"), Colonel K interrupts his attempt to set a record score with a call for an assignment.
* ''Level 257'', a Pac-Man themed eatery/bowling alley/arcade located in Schaumburg, Illinois, references the Kill Screen in its name (the level ''after'' the Kill Screen) and features a wall decal featuring the kill screen graphic. On the same wall is a lone Pac-Man machine permanently set to level 255 that features the kill screen when the level is completed.
* In the ''Series/HowIMetYourMother'' episode "Little Minnesota". Marshall takes Robin to his eponymous Minnesota-themed bar, where she finds a "Fisherman's Quest" arcade game, on which he has all the top scores. When she threatens to beat his top score and risk a "Gill" screen, he outs her as Canadian.
* The murder in one episode of ''Series/{{Bones}}'' had the suspect believed to have killed a rival "Punky Pong" player over which of them had played a perfect game until the kill screen. Virtually all of the video game information in the episode was wrong, and the "kill screen" referred to was one where the game ended because the player character [[LiteralMinded murdered the game's villain]].
* In ''Film/CloakAndDagger1984'', secret military information was encoded in the kill screen of the video game adaptation of the titular game. The responsible parties attempt to kill the kids who discover this, rather than [[EvilOverlordList killing the idiot who hid the plans]] [[TooDumbToLive where they would be quickly and inevitably discovered]].
* One [[MemeticBadass Chuck Norris Fact]] claims he's actually beaten Pac-Man and seen the real ending screen.
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