Randomly Generated Levels

This is when a Video Game generates a map, dungeon or level in a random (or, at the very least, unpredictable) fashion. Rather than seeing the same level designs over and over, the player gets a slightly different experience every time he plays. Roguelikes and Endless Running Games are the main users of this technique. Can lead to bad level design and bad gameplay if the maps generated are frustrating, terrible or likely to lead to other complications, but a good level generator can make the game interesting for more time and not being based on memorizing.

There are two methods of level creation that are generally used: the random generation and the random assembly. The random assembly means that the generation algorithm picks the manually-created assets from the game database and creates the level by stiching them together, while the random generation implies that all the content is created on-the-fly. The random assembly is easier to implement, but the limited number of the assets will become a sore in the eye sooner or later. The random generation is much more robust, but the complexity of the algorithms makes it almost unusable for anything more complicated than the level geometry. The middle ground in that case is to use the random generation for the basic level outlook, and to place the assets whithin it in the appropriate places.

Usually the computer will impose some restrictions on this randomness, so that, for instance, there is always a path to the end of the level, and the harder monsters won't appear while the player character is at a low level. Since the designer's choices in this area often have a bigger impact on the experience than the random elements do, this trope is also called "procedurally generated levels".

Some games allow to save/load or display/type in the pseudorandom seed to generate a map you wish to replay.

There are also games that use a fixed seed, so the player gets to play the same world every time. This technique is used in games that contain a game world that is much larger than the memory or disk space it is supposed to fit in.

When this happens to items and equipment, see Randomly Generated Loot.


Video Games with changing seeds (The levels are randomly generated each time you play)

  • Aztec, for the Apple IIe. Each time you would get a random arrangement of preset rooms and a random collection of beasties, tribesmen and chests. Problems with the layout were eased by using dynamite to blow holes in the walls between rooms.
  • Azure Dreams for the Playstation randomly generates the floors of the monster tower everytime you go to one.
  • Dark Cloud and its sequel, Dark Cloud 2, were quite fond of this. Could be infuriating when it came to speed runs and spheda.
  • Chunsoft's Mystery Dungeon games, including Torneko no Daibouken, Shiren the Wanderer, Pokémon Mystery Dungeon and Chocobo's Mystery Dungeon.
  • Minesweeper randomly generates the board after the first click. This can create situations where guessing is the only viable move because there are no sentient level designers.
  • Diablo features randomized dungeon layouts which include a handful of required rooms.
    • Diablo II does the same, though single-player maps do not change unless the original is deleted, or if the player plays online. These levels were more random before the first few patch; later on, they changed the random generator to be less annoying.
    • Diablo III's outdoor areas have a more regular but still randomized layout, with landmarks such as bridges, major dungeons, and paths to the next area always in the same place. Dungeons are totally random but built out of modular rooms instead of a crude assortment of walls like in Diablo II and II.
  • NetHack
  • SimCity
  • The Civilization series has this trope, though you also get the option to play on an Earth-like world. Even in the Earth-like worlds, you can choose to have both the resources and the nation starting positions randomized, leading to some very weird situations, such as being the Aztecs in Spain sailing off to conquer the Spanish in Mexico.
  • ToeJam & Earl, when playing on the Random World setting (as opposed to Fixed World, which just uses a fixed seed (see below)).
  • The first two Dragon Quest Monsters games. In the sequel, there were predefined "main" worlds and the sub-worlds were randomly generated; in the original, all worlds were randomly generated.
  • In Pikmin 2, the caves are created this way. The shape of the sublevels remains the same, but where the enemies, walls, treasures and other stuff are placed changes with each sublevel (with a few exceptions).
  • Infinite Dungeons official module for Neverwinter Nights.
  • Battle for Wesnoth allows for randomly generated maps. Also, two of its campaigns have randomly generated maps (one in each). Random cave maps, however, tend to favor chaotic units far more than lawful units, as the cave generator doesn't make any lighted spaces yet.
  • The Command & Conquer series allows for randomly generated multiplayer maps.
  • F-Zero X has a mode where you play in randomly generated tracks, sometimes with sadistic results. In a few cases, the X Cup will generate a track the AI cannot handle at all. Witness this track, where the competition manages to completely wipe itself out in ten seconds.
  • With the exception of your own base, X-COM: UFO Defense's levels are randomly generated based on pre-existing bulks of tiles (for instance, buildings).
  • Age of Empires took it to the extreme by letting people script the terrain generation.
  • Empire Earth's skirmish mode featured random terrain, though it was possible to choose the type (Islands created an archipelago, Mediterranean had a huge landlocked body of water in the middle, etc.).
  • Hellgate: London has this as one of its features - not surprising, since many of the developers came from the team that made Diablo.
  • Spore - Initially planets are generated and randomly populated with creatures, then an entire galaxy of planets and space civilizations.
  • Dwarf Fortress randomly generates every starting world. This being Dwarf Fortress, it also generates the history and legends of the land and tends towards realistic landscapes. Nothing like the taste of geology in the morning! It's possible to save and manually set the various random seeds to generate the same world on another computer, but significant changes in world generation prevent the same seed from being usable in different major versions.
  • All dungeons in Lufia: The Legend Returns are randomly generated. The Ancient Cave starting in the second game consists entirely of randomized floors in each game.
  • Persona 3 randomly generates most of the non-boss floors of Tartarus, although it follows a few design rules. For instance, floors between a Tartarus Boss and a plot-determined barrier will invariably be smaller than the norm, and the party will usually appear extremely close to the stairs to the next floor (with the small inconvenience that The Reaper will spawn that much faster, too.)
    • Persona 4 does the same thing with its non-boss floors, though there are one or two premade floors without bosses on them in the game.
  • Invisible, Inc. has a few rooms that are mostly the same in each level, but most of the rooms - and the level layout - are completely random.
  • The Worms series allows players to battle on randomly generated maps.
  • The Bonus Dungeons in Nippon Ichi games are like this.
  • In SWAT 4, the layout is always the same while the people in the buildings are placed differently every time.
  • Spelunky is a rare Platform Game example.
  • COMPUTE!'s Third Book of Atari includes the Atari BASIC source code of a game called Castle Quest, in which each room has random placement of walls and enemies.
  • Rise of the Triad bundles a program with the registered version called RANDROTT for generating random levels. Pick different parameters and a different seed value for a different set of levels. Quite a few user-made levels available online are actually modified RANDROTT levels.
  • Every level and world of Infinite Mario Bros. is randomly generated.
  • In Minecraft, by the same developer as Infinite Mario Bros., this trope is taken to ridiculous levels: The random level generator is used to produce levels larger than the entire surface area of Earth.
  • Water Warfare randomly generates all its maps, though in each of the four map themes (Playground, Beach, Plaza, and Nature Park), certain features will always be consistent. Certain templates will also show up with reasonable consistency based on map size (small or large), game type (Battle Royale, Deathmatch, Treasure Chest, Checkpoint, Point Rally, Defender), and number of players (two to eight). For example, a 1-on-1 Battle Royale on the Playground will always have two hills and no underground tunnel, but adding just one more player allows a tunnel to appear. But no matter how many players are added to a Treasure Chest battle, if it's on the Playground, there will never be a tunnel. (In Mission Mode, however, the maps are always the same for each mission, and not random at all).
  • Yoda Stories.
  • The Microprose game based off Magic: The Gathering has a randomly generated map. Enemies are encountered randomly. Dungeons, where you get random cards, are generated randomly and appear in random locations. Enemies attack towns randomly; if you did something for that town to give you an extra hit point, you lose it if you don't stop them; if one wizard (There are five, one for each color of magic.) takes over three towns (four if you have a special item), game over.
  • The dungeons in Recettear: An Item Shop's Tale are generated this way.
  • The original Castle Wolfenstein has pregenerated rooms whose layouts didn't change; however, the order and connection between rooms was randomized at the start of each game.
  • Runescape has the dungeoneering skill, which is firmly based on this trope.
  • The Inazuma Eleven series has training centers. The course consists of a rectangular grid of rooms with doors between them. You start at a random room in the bottom row, one (possibly more, but you're locked in as soon as you find one) random top-row room is designated as the goal and is larger than usual, and the two are always connected by a path through a series of unlockable doors. Aside from the goal room, each room also contains either a free item or a battle at the center, and picking up the item or winning the battle opens all unlockable doors in the room (from the side you're on only; doors can be unlocked twice, once from each side). Losing a battle kicks you out, while reaching the goal room pits you in a full-fledged soccer match which gives everyone on your team a permanent stat boost if you win. Each time you play, the set of unlockable doors and each room's contents are randomized. As you progress in the main story, the grid gets bigger, the battles get harder, the item drops get better, and the stat boosts for clearing the whole course are also increased. Additionally, the layout tends to vary based on the course you pick (which determines which stat(s) get boosted if you win); the Stamina Course in particular tends to have the path snake around and go through nearly every room in the grid, with branches leading to dead ends being few and short, while some others tend to have maze-like layouts.
  • Tales of Symphonia has Niflheim, while its sequel has Gladsheim. Both consist of nodes on a rectangular grid with connections between them. Niflheim is a timed 15-level dungeon with no save points, and each level requires you to either defeat all enemies on it or find the exit. Gladsheim is an untimed 10-level dungeon with a save point on the third and sixth levels next to the entrance, and the 10th level has a boss fight and nothing else. Apart from the 10th level, each level is an 8-by-8 grid; you start on a random non-edge square and have to go to all 4 corners and defeat the enemy at each corner.
  • Terraria can randomly generate maps several times larger than the application itself.
  • Get Medieval had a game mode that would randomly generate dungeons.
  • Canabalt
  • Robot Unicorn Attack
  • Temple Run
  • Oasis has randomly generated levels based on the difficulty, campaign and level.
  • In Space Panic, the ladders connecting the platforms were randomly placed.
  • Ten Minute Space Strategy generates a new map for each campaign, with size and planet density decided by the player.
  • This was a selling-point feature of Slayer on the 3DO Interactive Multiplayer, as the box proudly touts the ability of the game to create over 4 billion different dungeons.
  • Burning Rangers has only four levels, so SEGA used this trope as a way of boosting replay value. And how, because there are tons of variations. You can even unlock codes for each specific version of the levels that let you play that version as much as your heart desires when you use the codes.
  • Aqua Rhapsody
  • Super Hexagon
  • Indiana Jones and His Desktop Adventures and Yoda Stories are unusual Adventure Game examples, where not only is the terrain created randomly each time, but the puzzles and items are drawn from a large pool.
  • Torchlight has a library of human-designed set-piece puzzles and mook gauntlets, which it randomly arranges on each level, and fills in the gaps with procedurally generated corridors and rooms.
  • One of the main ideas underpinning Starbound is to take this as far as possible - it's set in a universe where all planets are procedurally generated and totally unique, from obvious things like the size, climate, biome, and number of moons, to even things like the day/night cycle and gravity level. And not only are the planets procedurally generated but the plants and animals as well. So much is generated that the possibility of any two players getting anything even close to the same planet is statistically impossible.
    • Notes from the developer have suggested that between random starting locations and each player having their stars spawn randomly across the map, everyone's experience will be unique. However, the star's precise coordinates form its seed, so players can share their finds by giving each other these (long) numbers.
  • Rogue, the very first roguelike and the inspiration for all subsequent roguelikes, including Diablo.
  • Dungeon Hack, an unusually forgiving roguelike with Eye of the Beholder look and feel (and also using AD&D 2nd edition rules and published by SSI). Included an option to display and manually set the random seed.
  • Diggles: The Myth of Fenris is an odd case. The map is generated not at the start of the game, but when you order to explore a part of a dark area. And only for the area you order to explore (or a slightly bigger area if you luck onto a plot-advancing large cave). Thus reverting to an older saved game may result in a radically different map.
  • Warlords turn-based strategiesnote  starting from II have the "Random Map" option.
  • In Ragnarok, almost all the levels have a random layout, save for a few very specific locations.
  • Many games by ABA games utilize these.
    • rRootage normally has fixed stages, but the R stages have randomized patterns.
  • The dungeons in Arcuz II are randomly generated each time you load your save.
  • The defining feature of Daylight compared to other first-person horror exploration games (i.e. Slender: The Arrival, Amnesia: The Dark Descent, Outlast) is that the maze-like levels are randomly generated each playthrough, adding replay value.
  • The castle in Nosferatu The Wrath Of Malachi is semi-randomly generated each new game. The basic layout of the castle remains the same, but the interior rooms and the placement of enemies and NPCs differs each time.
  • SCP - Containment Breach features three zones, all of which have random layouts, most of which are filled with monsters that will kill you in a variety of ways.
  • X3: Terran Conflict and the expansion pack allow players to earn a unique upgrade for their ship which allows it to activate a Blind Jump and jump off of the Portal Network. Unlike normal sectors which are designed by hand, unfocused jump sectors are completely randomly generated. The Unfocused drive typically dumps the player into intergalactic space with occasional Xenon or Kha'ak enemies, and the sectors are the only way to "acquire" the unique Goner Aran mothership.
  • Super Smash Bros. for Wii U/Nintendo 3DS has the "Super Mario Maker" stage, where the layout is random and continually changing.
  • Warframe assembles the layout of missions from an assortment of tiles created by the developers; the mission chosen affects which tileset and which specialty rooms (e.g. Spy vaults), if any, are used. There are a few exceptions, such as quest missions and raids, which use predetermined layouts instead, but regular missions always have a random layout.
  • Pokémon Diamond/Pearl/Platinum has Turnback Cave, home of Giratina (though in Platinum, you'll only have to go there for Giratina if you failed to obtain in the Distortion World). Each room has four exits, and there are 25 different room configurations (not including Giratina's room). One of these is the "pillar room"; you must find this 3 times before entering 30 total rooms, and then any exit from the third pillar room will lead to Giratina's room (or after Giratina's been captured, an item room). Other than the third pillar room leading to the end and the 30th room leading to exiting the cave if you haven't found three pillar rooms, it's completely random what exit will lead where. note 
  • Final Fantasy XIV has the Palace of the Dead where each floor has a different layout every time you enter the palace. Each floor will always have a spot that advances you to the next floor and a spot that is used to revive fallen players, but traps and treasure coffers will always be randomized. Each set of 10 floors has its own set of enemies.
  • Soldier of Fortune II's Random Mission Generator generates maps from pseudo-random seeds that can be chosen by the player.
  • In Wilderness: A Survival Adventure, the Ur-Example of the Survival Sandbox genre, the player can either play on a "starting map", or procedurally generate a map.

Video Games with fixed seeds (The developers randomly generate a level, and put that level on all copies of the game)

  • Elite:
    • The game has eight galaxies with 256 procedurally generated planets each (2,048 in total). The seed for generating a galaxy is 48-bit, and the game was initially going to include a galaxy for every possible seed value (282 trillion galaxies with 72058 trillion planets in total), but they thought that would be overkill. The developers had problems with the mere 2000 they chose. First they had to rewrite the seed several times when it generated planets with obscene names and second there are a few systems that, if you arrive at (Via the hugely expensive, one use, intergalactic hyperdrive), you can never leave because they are too far from other systems.
    • Frontier: Elite II fits a galaxy of 100 billion star systems on a 3.5" DD floppy. All of this is procedurally generated apart from a small scripted islet which contains the planetary systems of Sol and many other familiar stars.
    • Elite Dangerous likewise has a full galaxy of over 100 billion stars, each with its own planetary and ring systems and sometimes extra suns. A few hand-designed and hand-modified systems exist, such as Sol, and some systems have unique descriptions, but otherwise everything is procedural.
  • Infinity: The Quest for Earth was set to use procedural generation to create billions (literally) of different star systems (including stars, planets, moons, and so on). Since this seed was going to be always identical, however, every player would see the same universe.
  • The Elder Scrolls
    • Arena and Daggerfall have, with a few hand-crafted exceptions, thousands of procedurally generated towns, cities, villages and dungeons. Arena does this on the fly, while in Daggerfall, they were generated on the developer's computers, then placed on the disk.
    • Morrowind downplays it, as the entire world is hand-built, but some of the dungeon architecture still gives the impression that they may have been randomly generated during development. The extremely limited Level Scaling of enemies and loot further reduces the randomness.
    • Oblivion and Skyrim do this with parts of the landscape, and have the same dungeon architecture feel of Morrowind, but play it straighter in that the enemies and loot within are determined via Level Scaling.
  • Starflight may have a scripted overworld (although the star systems feel quite random-generated), but at least the planetary maps are generated.
  • The Sentinel has 10,000 unique levels (or "landscapes") and still fits in the 48K RAM of ZX Spectrum. The original version of The Sentinel was written for BBC Micro. Depending on the model the amount of RAM could be 16, 32, 64 or 128 kilobytes. So, if the BBC version ran also on Model B (which had 32 kilobytes), it could mean that the versions for C64 (done by the creator of the original BBC version himself) and ZX Spectrum (done by Mike Follin) don't even come that close to using the entire RAM of their respective platforms.
  • The Explorer, an obscure 8-bit computer game, is the extreme example in the 8-bit world with its 4 billion unique locations.
  • Noctis is a space-simulation game which generates a galaxy with a radius of 90 thousand light-years. The entire purpose of the game is explore it and upload findings into an online guide so that others might find them.
  • Sonic the Hedgehog 3 and Sonic 3 & Knuckles have bonus levels that have you running around touching all the blue spheres (which then turn red) and avoiding red ones. Lock-on Sonic & Knuckles with any non-main-Sonic game made before it, and you'll get a Sonic 3 style bonus level unique to that game, and other copies of the same game will play the same stage. The idea is that gamers will want to check out their whole library of games for bonus stages, but this was an unadvertised feature, possibly because it didn't work with games made after Sonic & Knuckles. There are a lot of different bonus levels to find, but there's even more if you connect S & K to the original Sonic The Hedgehog, which has more than 134 million levels (don't get too excited though, repeat levels start appearing after a mere 120 million), and lets you revisit ones you've already played through passwords.
  • The .hack games have dungeons created by selecting a group of keywords, which are generated from those keywords, except for a few plot-critical dungeons.
  • The grottoes in Dragon Quest IX
  • Several games by cactus' feature levels (or rather bosses) generated with a fixed seed. These include Protoganda, its sequel and Burn The Trash.
  • Several games created by Lucasfilm in the early 1980s used fractal technology to generate maps of then-unprecedented complexity:
    • Behind Jaggi Lines! was a beta version of air combat simulatornote  over ragged mountains.
    • Rescue on Fractalus! was a polished version of the former.
    • The Eidolon simply turned the mountains upside down making them the insides of a cave.
    • Koronis Rift was about piloting a surface rover over a jagged terrain. It had somewhat better graphics.
  • No Man's Sky, much like Noctis, creates an entire explorable universe this way with about 18 quintillion planets, where everything is procedurally generated.

Non-Video Game examples

  • Each case in WHO dunnit has a killer randomly selected from a pool of five suspects.

Web Animation
  • Each fight during Vytal Festival Tournament in RWBY takes place in a randomly generated arena, combining several terrain types like forests, mountains, hills or ice. The amount of terrain types depends on the round - team battles have two "zones", while doubles have four. It becomes subverted once we learn that Cinder is manipulating the draw.

Web Comics

Tabletop Games
  • Many tabletop RPGs include systems of randomly generating dungeons. Likewise, there are many third-party programs designed to generate random dungeons for tabletops. (One for D&D 3.5, for example: http://donjon.bin.sh/d20/dungeon/ )
  • One of the two realities in the game The Splinter is an infinite, randomly generated fantasy dungeon. The rulebook contains plenty of random dice tables to generate a tiny fraction of this infinite dungeon for the players to explore.
  • Betrayal at House on the Hill features randomly generated layouts, chosen randomly by the players as they are playing the game. Also, the same could be said of the Betrayal itself as it's based entirely on what the players find by exploring the House.

Alternative Title(s): Randomly Generated Level