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!
Yep, the Kill Screen, enemy of completionists of yore. The result of an Endless Game being played for such a long time without a Game Over, and the player advancing so far that an internal counter (like the current level number) reaches its inherent limit (often 255 or some other similar number) and "overflows" (e.g. resetting itself back to zero), causing a Game-Breaking Bug 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, 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 Unintentionally Unwinnable, although the act of merely reaching the Kill Screen may be considered (in and of itself) a form of victory.
Compare and contrast Minus World, a level that is found by exploiting a glitch and is at least semi-playable, rather than breaking the game outright.
Actual Kill Screens:
- 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 Google's Pac-Man Doodle references it. Also the "Forbidden Maze" in Pac-Man and the Ghostly Adventures 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. 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 Ascended Glitch 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 Advancing Wall of Doom in the form of the unreadable garbage from Stage 256.
- Happens in Donkey Kong, in which the overflow sets your death timer to 400note . Very few have gotten there legitimately, as shown in the documentary film The King of Kong. 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
- As demonstrated in this video, once you make the grueling effort to reach the 133rd stage of the NES version of Donkey Kong Junior, the game will start to behave strangely by playing 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
- After clearing round 255 of Dig Dug, 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.)
- Heroes of Might and Magic 3 had a glitch that would crash any game after the third "month" of play. This was corrected, though.
- 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 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. 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 RC Pro-Am, the 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 Duck Hunt, 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 Galaga, clearing 255 stages will yield Stage 0, which crashes or soft-locks the game unless the DIP switches are set for the toughest difficulty level, giving us an example of Kill Screen crossed with accidental Easy-Mode Mockery.
- Many games from the infamous Action 52 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.
- Bubble Bobble Revolution was unwinnable because the boss of Level 30 failed to spawn. Notable in that this was not an Endless Game. However, this issue only affects the initial USA release of the game; the European and Japanese versions don't have this issue.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 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 Existential Horror-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.
- rymdkapsel's endless 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 SNK arcade game Sasuke vs. Commander freezes right as you begin to enter the 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 freeze in place(if your shuttle was oriented straight up when you hit the cap), or you 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 the sky trying to be the ground before the game locks up and forces you to refresh.
- Pango, a DOS Pengo clone, crashes on level 49 due to a divide by zero error.
- In BurgerTime, Level 28 is considered the killscreen. The baddies explode into manic hyperactivity, and if you survive for a nearly-impossible 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 Missile Command 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 Pinball Scoring in Video Games.
- 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 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 never bothered to put in something at the end of the level to congratulate the player, the only thing that'll happen if they do beat it is to get sent back to level 1.
- Arkandian Legends: 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.
- Call of Duty: Zombies:
- The Treyarch-produced Call of Duty: Zombies 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 Good Bad Bug for giving players an unintentional set of 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 Gladiator (Great Gurianos), the developers ran out of memory to program the ending, so they intentionally made the final opponent unbeatable.
- Dogyuun is supposed to loop indefinitely as with most 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.
- Bosconian is, like most Namco games, meant to loop after awhile with top speed. However, 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 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 . On stage 257, however, the screen will be blank white (albeit the music is still playing). 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 rushed Commodore 64 port of 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.
Parodies, references, and Lampshade Hangings:
- In Episode 5 of Strong Bad's Cool Game for Attractive People, 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 to increase Professor Pineapple’s fire rate to maximum, then swap the bins containing damaging fruit and scoring fruit.
- BioShock 2'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, a large R and a golf club.
- The back cover of 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 Chuck, the nerd must get the secret codes to a Cold War satellite by getting the Kill Screen in Missile Command.
- The webcomic 2P Start referenced the Pac-Man kill screen in one comic.
- The high-brow gaming magazine Tom Clancy's "Kill Screen" is named after this.
- In White Devil of the Moon, 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.
- NCIS had an episode built around the Kill Screen as a theme. The Victim of the Week had encoded vital information into it.
- On an episode of The Venture Brothers, Henchman 21 despairs at having seen everything life has to offer. He lists "the Donkey Kong kill screen" alongside "attack ships on fire off the shoulder of Orion".
- Parodied in Filibuster Cartoons here.
- The Stinger Logo Joke to Wreck-It Ralph features half the Walt Disney Pictures logo getting changed into the Pac-Man kill screen.
- As Danger Mouse 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 How I Met Your Mother 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 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 murdered the game's villain.
- In Cloak & Dagger (1984), 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 killing the idiot who hid the plans where they would be quickly and inevitably discovered.
- One Chuck Norris Fact claims he's actually beaten Pac-Man and seen the real ending screen.