Video Game / M.U.G.E.N

It's so simple, yet so complex. It's the perfect Fighting Game formula! HUEHEHEHEHEHEHE! ^{Click here to see the previous official Winmugen menu}

"Victory means nothing when we're fighting everything."

—Mondegreen of Loading screen in the "Infinity Mugen Tournament" motif.

"Mugen" is Japanese for "infinity". M.U.G.E.N, however, is a freeware 2D Fighting Game engine designed by Elecbyte, written in C with the Allegro library and originally released in July 1999. Beta versions of the engine were made to work on DOS, Linux, and Windows platforms, all of which were distributed through their website.

At its core, the M.U.G.E.N engine allows users to import created characters, background stages, and other game objects through interpreted text files, graphics, and sound compilations to create a functional fighting game similar to commercial games produced by Capcom or SNK. While the engine is set up primarily for fighting game development, developers have used it for several other game types (including shooter and platform style games). Elecbyte officially claims to have forgotten what the acronym M.U.G.E.N stood for, but the readme documentation says its meaning referred to the days when the engine was meant to emulate shooting games instead of fighting games.

The engine allows anyone with the resources to create and import characters, background stages and other game objects. It even supports various types of audio formats (mainly MP3 and MIDI, although it can be configured to play various audio formats via Winamp plugins) so that players can have a soundtrack. Since M.U.G.E.N allows for most of the same types of functionality found in most commercial 2D fighting games, players can basically recreate any of those games' characters and gameplay—which is where the real appeal of the engine lies.

A vast majority of the first wave of M.U.G.E.N sites have either not been updated since 2010 or have been shut down. Because of this, finding certain characters that have become infamous within the M.U.G.E.N community is a near-impossibility without the use of "warehouse sites", which try to contain as many characters as possible.

DOS and Linux versions

First released on the 27th of July 1999, M.U.G.E.N was initially created for MS-DOS. Development of the DOS version ceased when Elecbyte switched to the Linux platform in November 2001. For a time, Elecbyte had a running request for donations on their site to legally obtain a Windows compiler so they could make a Windows version of M.U.G.E.N. The development group discontinued this project in 2003 and shut down their site. Speculation has since pointed at leaks made public of a private Windows-based M.U.G.E.N beta that was provided to donators.

Windows version and subsequent hacks

The private WinM.U.G.E.N beta contained a two-character roster limit, locked game modes, and nag screens. With the beta leaked and Elecbyte gone, a "no limit" hack that removed most of these limitations was made available in 2004 by Rou Hei, followed by subsequent updates to deal with bugs and other issues. This version of M.U.G.E.N is functionally the same as the last Linux release, though with subtle differences and unique issues (mostly revolving around proper music and music plugin support). Due to the changes between the DOS and Linux versions of M.U.G.E.N, many older characters required at least the SFF files to be modified so the engine could display palettes correctly (notably on portraits). This version also had some changes in how certain CNS script controllers functioned, which caused some minor upset amongst the community. Those that could still run the DOS version in some form stayed with that version and even offered DOS patches to downgrade characters for compatibility with the older version.

In May 2007, a hacked version of WinM.U.G.E.N was released by a third party; this hack added support for high-resolution stages (such as those seen in Guilty Gear X) at the cost of losing support for standard resolution M.U.G.E.N stages. Later that month, another hack was done to add support for high-res select screens. In July 2007, another hack—this one created by Sion and Kung Fu Man, based on the last high-res hack—allowed for only the select screen to be high-res, not the stages. In December 2007, a hack from an anonymous source allowed both low-res and hi-res stages in the same build, with only a single line of code necessary for the hi-res stage support.

Elecbyte's website and the return of the M.U.G.E.N engine

In mid-2007, Elecbyte's site returned, though not without some controversy as to its legitimacy, as it only showed a single logo with Google ads on the side. On the 26th of July, a FAQ was added to the site, which claimed that Elecbyte would release a fixed version of WinM.U.G.E.N before major format changes in the next version. Those formatting changes would supposedly remove compatibility in regards to older works: "Do not expect old characters to work. At all."

Despite some widespread agreement in the M.U.G.E.N community that the new site was a fake, things changed around two years later when a new release candidate, MUGEN 1.0, was added to the site. The 1.0 version offered Open GL support as well as proper HD display options, victory quotes, and improved stability as a whole. The supposed widespread incompatibility of older works was never a problem; Elecbyte took steps to ensure that properly-coded characters would not malfunction in the new engine (or would require minimal updates), though screenpacks were not necessarily subject to the same rule. MUGEN 1.0 left the "Release Candidate" stage in January 2011; MUGEN 1.1 was eventually released in August 2013. There have been no updates to the engine since then.

Clone projects

When development of the WinM.U.G.E.N engine stopped, several clone projects started to try duplicating the engine's functionality from scratch. These projects include ShugenDo, InfinityCat, xnaMugen, and Open Source Mugen. Some of these alternatives presented online gameplay capabilities, a feature many users wanted for years. M.U.G.E.N clones currently in development include IKEMEN GO and Paintown.

For more information, check out these websites:

• Elecbyte's website. Note that Elecbyte's Website now returns a 403 Forbidden error (confirmed as of the 26th of March 2019). Here's the last archived site thanks to Wayback Machine.
• The Mugen Fighters Guild - This is the starting point for many M.U.G.E.N players. If you are using M.U.G.E.N for the first time, this should be your first stop. Their forum is one of the largest communities on the internet and one of the few older ones that didn't go offline. Also have their own Database, but it's discontinued since 2016.
• Random Select - This site houses a huge database for characters and stages as well as the BIJIN engine, an offshoot of the M.U.G.E.N clone IKEMEN. Offline since 2019, is also archived thanks to Wayback machine and with avaliable downloads.
• Trinity Mugen - Created by Vans, Jesuszilla, and Fusion around 2005, the site is pretty much what its name suggests. It is the home of many a worthwhile M.U.G.E.N character, and it will even provide hosting services if necessary. The forum does not see much activity, as most of the action is at the IRC chat.
• http://mugencharacters.ucoz.com - This is one of the larger databases of M.U.G.E.N characters available today, with just about every character ever made (including some that are otherwise all but impossible to find at all). That also means it has just about every character ever made. Additionally, it hosts its own copies of everything, which annoys no small part of the community; CTRL+F "Warehousing" below.
• http://mugenchara.blog.shinobi.jp - This is a Japanese M.U.G.E.N blog with a character/stage entry added nearly everyday. It only links content to their original downloads. A translator tool is required for most users. Outdated since 2015.
• SaltyBet - SaltyBet is like betting on boxing or MMA fights... but instead of betting on when Mike Tyson is going to knock someone out, you get to bet on who would win in fights involving magicians who beat you up with dolls and lasers (sometimes both), Superman, robot ninjas and undead ninjas who brutally murder their opponent, crossdressing nuns, princess vampires, robot animals, killer mecha, a children's mascot with an assault rifle, a fat pink demon, human aliens, and fancy golden-haired aliens who spew poorly-ripped, badly-acted Spanish. (Oh, and Mike Tyson.) SaltyBet uses a modified M.U.G.E.N setup to play a continuous stream of randomized matches picked from a roster of literally several thousand characters, and visitors to the site can register to bet on who will win a given match. The money used to bet on these matches is not real, but the salt produced by these fights sure as hell is. The site also features a pay-(real-money-)for premium service—the Illuminati—that allows bettors to access the site's Compendium, which contains character statistics and matchup odds that can help them make better bets. Check out the site's FAQ for more information, and remember: Always never bet on DBZ...sometimes.
  • Also they have their own wiki, the SaltyPedia, being not just focused on characters appeared on SaltyBet, but also serves as a database for creators and fullgame projects.
  • SpriteClub - SpriteClub can be considered a free offshoot of SaltyBet that is arguably better features-wise in a number of ways. The website provides the ability for viewers to submit any of their characters, stages, and music tracks for addition in monthly engine updates. SpriteClub also gives users access to view individual character/stage/playlist statistics, a page to create live customized exhibition matches, and the ability to host up to 4v4 rotation battles. SpriteClub has a much smaller user base than SaltyBet, but is considered to be more transparent and open for M.U.G.E.N content creators.
• MUGEN Database - This database, which runs on a Wikia template, is one of the more up-to-date websites; it focuses on archiving and providing sources for characters and stages.
• Mugen Free For All - This is another community that focuses on archiving materials for the engine, providing detailed directories of characters and stages that are kept as up-to-date as possible. The members of this group are adept at finding those hard-to-find creations that no one else can, and unlike most archive sites, it is also home to a group of creators and their own original creations. Actually it's the second large M.U.G.E.N. community online after Mugen Guild, also sharing various users and creators from that forum.

For the sake of keeping this article from becoming another list of character tropes, please avoid adding entries for characters which are not exclusive to M.U.G.E.N, as tropes associated with pre-existing characters from other media can have theirs listed in the appropriate areas.

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M.U.G.E.N-based games with their own pages:

• Anti-Gouki Project
• The Black Heart
• Card Saga Wars
• Castlevania Fighter
• ClayFighter: Infinite Clayfare
• Hyper Dragon Ball Z
• Kakuge Yaro (diverse remakes like Project Lensman)
• Rumble Pack
• Sango Fighter Special Edition
• Saturday Mornin Mayhem
• Touhou Gensokyo Reloaded
• Vargverse
• VHFSMACVUSMRRM ^note  Short for Vargskelethor's Hardcore Friday Super Metal Almost Criminally Violent Ultra Swedish Meatball Royal Rumble MASSACRE!

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The M.U.G.E.N engine, its community, and even some games made with the engine include the following tropes:

A-C

• 2½D: Zig-Zagged. Although the engine itself is 2D, there are several characters that use 3D models, albeit rotoscoped to 2D sprites. IKEMEN features compatibility with true 3D stages with 3D models, but gameplay is still generally confined to a 2D plane.
• Action Initiative: Like most Fighting Games, attack priority returns as a mechanic, and it's possible to code attacks with higher or lower priority (or even infinite priority such as an Invulnerable Attack).
• Adaptational Badass:
  • Any character who was a non-combatant in their original source material can throw down like never before in M.U.G.E.N.
  • If character edits are included, then already strong characters can become even more badass.
• Adaptation Inspiration: The variety of characters adapted to M.U.G.E.N is wide, most of them not just adapted from fighting games, there are characters adapted from other games, mostly platformers, but there are other exceptions like being adapted from RPG, characters from cancelled games, and even characters that never appeared in a video game.
• Adaptational Wimp: Inversely, some characters have different versions that are much weaker than the source material (whether it be intentional or because they're shoddily made).
• Aerith and Bob: When you have a crossover between as many games as can be imagined (and original characters), this is going to happen.
• A.I. Breaker: Some types of characters (e.g., mob-type characters, massive boss characters) have a tendency to confuse AI-controlled characters.
• Amazing Technicolor Battlefield: When projectiles, clothing, and the background tend to be all the colors of the rainbow, this is bound to happen. Even drab or grim stages can get colorful real quick.
• Amazing Technicolor Population: With custom palettes, this is possible for just about anyone.
• Anachronism Stew: When you have characters from fighting games that take place during different time eras, this happens.
• April Fools' Day: There is a tradition in the M.U.G.E.N community about releasing Joke Characters on this day to fool players. Many such characters are surprise characters that people do not expect, while others that are supposed WIPs are fake, and a few only make the release post in forums but have no download.
• Art Evolution: A creator's artistic ability may grow as they continue making characters, this is especially notable if the creator remakes one of their older character.
• Artificial Stupidity: Several characters lack an AI, which makes them use the MUGEN Engine's AI. This consists of them using random moves and attacks for the most part, which usually tends to be ineffective compared to a custom made AI.
• Ascended Extra: Due to the nature of the game, it's possible to play as extremely minor characters and give them the same level of relevance as established main characters.
• Assist Character:
  • Some characters have built-in assist characters (usually referred as Strikers, the name for such characters in The King of Fighters). Some have them because they had them in their source game, but the majority of characters with built-in Strikers have them because of the M.U.G.E.N engine's limitations.
  • The Uno Tag and Add004 systems lets you do this with many characters, and IKEMEN has a mode that allows you to do so directly from the engine itself.
  • This is doable so long as there is a proper application of art and hitboxes. Some stages also allow you to do this.
  • It is possible to edit the .def file of literally any character you have, and most of them have a "scale" option. This can result in you beefing up the size, and therefore hitboxes and attacks, of anyone. A fifty-foot-tall Kung Fu Man who is so tall that he is going off screen? Par for the course in M.U.G.E.N.
• Author Appeal: There's various characters in the community that are made to suit the maker's personal tastes. Expect several references, cosplay, and fanservice if you're playing a character that isn't a direct adaptation of another fighting game.
• Awesome, but Impractical: Many new screenpacks are High Resolution and have stylistic portraits and icons in their select screen and lifebars, but most characters don't have portraits or icons designed with them in mind. Therefore, you must use a (hopefully provided) select screen template, and manually add them in as well. It's an easy task for a small roster, but almost impossible for a bigger roster!
• Background Music Override: It's entirely possible to have a character play a music track that replaces the stage's normal music (provided it has any).
• Badass Normal: Anyone who does not throw fireballs/shoot lasers/mutate/use magic can beat up homicidal robots, killer aliens from outer space, evil psychic projections made from two mutants that happens to be bigger than a skyscraper, actual Gods, and Mike Tyson. Kung Fu Man is one of the normals, since he does not have a single projectile attack, although he does have inexplicable Double Jumping ability.
• Batman Can Breathe in Space: M.U.G.E.N characters can breathe in stages located in the space.
• Beyond the Impossible: There are characters who can win a match before the match even starts, something that never occurs in any other Fighting Game. It is also a literal breaking of the game's rules, in the sense that their code overloads the game to the point where the opponent fails to load and is thus defeated.
• Big Bad: Suave Dude is the main antagonist of vanilla MUGEN and the one responsible for kidnappping Kung Fu Man's girlfriend and rallying all of the other characters in the roster against him. Although he never made a physical appearance for years.
• Boring, but Practical: The "template"/default character that comes with the game, Kung Fu Man. He lacks any projectile moves or special particle effects, simply using punches and kicks as a Badass Normal. However, his basic moveset with specials, supers, a throw, a Double Jump, and a Defend Command is adequate enough to take on the more flashier opponents if the player uses him well.
• Break Meter: Some characters have this. Characters with Guard Meters also have this.
• Chromosome Casting: Because of the engine's customization abilities, players can create a game with an all-female roster (Or at least, female-dominated), or an all-male roster.
• Combos: Combo attacks are extremely common among characters, given that it's a Fighting Game engine. There's an in-built code to make your attacks stop comboing once the hit counter gets high enough, in order to prevent infinite combos.
• The Computer Is a Cheating Bastard: One example is certain characters not requiring a minimum Super Bar level to do Super Moves when controlled by the AI, but requiring it when controlled by the player.
• Cool Versus Awesome: Given the fact that the game allows you to include characters and stages from every fighting game imaginable, this is inevitable.
• Counter-Attack: Several characters have one of these, and this mechanic can even be implemented via the Reversal or HitOverride codes. Notably, Reversal moves are capable of affecting characters without collision boxes, use HitOverride Hyper Armor, or use invulnerability via NotHitBy.
• Crossover: M.U.G.E.N is often used for this, although gameplay styles do not necessarily mix well.

D-L

• Damn You, Muscle Memory!: The possibility of a M.U.G.E.N build having characters from different source games (complete with distinctive control schemes of such) tends to confuse some players when they are getting to know or use new characters.
• Death of a Thousand Cuts:
  • There are many characters whose attacks will hit the 999 combo meter.
  • There are Shoot 'Em Up characters with insanely rapid-firing attacks that deal extremely weak damage. This trope often becomes their main method of combat.
• Deconstruction Game: M.U.G.E.N can be seen as a deconstruction of crossover fighting games (as well as games with guest characters), as you can see the far more realistic consequences of having characters in your roster with widely different gameplay rules.
• Decon-Recon Switch: Thanks to the customizability of the engine, you can rewrite the files and states of your characters for proper balancing.
• Depending on the Writer: If about two or more makers share the characters they've converted, don't expect them to be both exactly the same.
• Did Not Get the Girl: Happens in Kung Fu Man's ending, as he can't save his girlfriend due to his kidnapper, Suave dude, not being created as a character yet.
• Ditto Fighter: Characters that are designed to be Ditto fighters often end up with an attack style that is mostly a mishmash of attacks from other characters. This is due to the difficulty of a programmer actually creating a character that duplicates the moveset of another character.
• Divergent Character Evolution: There's the occasional instance of a character starting out as a spriteswap of another character, only for other creators to take said character and heavily differentiate them from their original counterpart.
• Double Jump: Several characters including the default version of Kung Fu Man are able to use this. One can even set the number of air jumps that a character can do. Cue fighters hovering over the stage for a full minute and duking it out above the camera's view.
• Downer Ending: Kung Fu Man's arcade mode story ends with him failing to save his girlfriend from Suave Dude due to him not being created yet by Elecbyte. There would later be multiple versions of Suave Dude this isn't acknowledged.
• Dramatic Disappearing Display:
  • Some characters have coding that hides the entire GUI (lifebars, victories, powerbars).
  • Also possible to do so manually through the debug keys- Hold Ctrl and press L, and the HUD will disappear.
• Early-Installment Weirdness:
  • The very first version of Kung Fu Man, for the DOS version of MUGEN. His sprite looked different, he only had a basic punch, basic kick, crouching and aerial punch/kicks, one Special, one Hyper, and his throw move was nonexistent/bugged.
  • WinMUGEN could be considered this to MUGEN 1.0 and 1.1, as it had some code that is no longer available or deprecated in 1.0 and above, such as the "TagIn" function, statetime as a possible trigger (which is identical to the "time" trigger) and z-width, z-position and z-velocity variables (indicating that it was likely meant to have a 3D-axis).
• Easter Egg:
  • Some fighters have special entrances with other fighters, and sometimes special ending poses.
  • Thanks to the 1.0 update, winquotes also can be directed to certain fighters.
• Excuse Plot: Kung Fu Man's arcade mode intro serves as this.
• Fan Remake: It's entirely possible in this engine to remake whatever fighting game you desire. There are even standalone M.U.G.E.N games that are practically near-identical copies of popular fighting games (often with some new elements added to them).
• Finishing Move: A character's Super Move will sometimes be used as this. Characters from games that have explicit finishing moves will have them as well.
• Foregone Victory: Certain cheap characters can exploit the system itself, causing them to win even before the match begins.
• The Fourth Wall Will Not Protect You: Taken to its logical extreme with "dragon-tier cheapies", which are less like characters and more like computer viruses that are capable of completely destroying your computer.
• Game-Breaking Bug: Certain matchups can lead to one character being unable to land a single point of damage on the opponent, both characters being unable to damage each other at all, or outright malfunctions in the engine, due to the different codes used with each character and/or sloppy coding. Some characters are intended to be used in standalone games rather than the regular engine and are outright not compatible, which can lead to infinite exploits by simply spamming projectiles or even regular punches.
• Game Mod: There are various mods and tools that can alter the M.U.G.E.N engine.
• Hitbox Dissonance: In some cases, the size of a character (or even the posture of their stance) may cause punches, projectiles, or other attacks to go right over their head, sometimes just barely. This can lead to those attacks being avoided by simply standing still. Then there are moments where it looks like a character should be able to avoid an attack by crouching, but the attack still hits them anyway. Oh, and if a character is running, depending on their size and the posture they take, the same situations can occur, meaning a projectile can hit or miss when it looks like it shouldn't.
• Hit Points: All characters have a HP bar which depletes when they're damaged. Certain characters however use this to show how many "lives" they have, such as the Shoot 'Em Up ships (getting hit takes off one of their three "lives" by removing a third of their life bar) or army/swarm based characters (where each individual character getting killed removes part of the lifebar).
• Historical Domain Crossover: Happens when you have crossovers between characters from fighting games and Real Life that take place during different time eras.
• Hold the Line: There's a few characters that task you with surviving for a certain amount of time instead of actually fighting them. Some of these use their own timer rather than the standard match timer, presumably to prevent the characters becoming impossible to defeat in situations where the timer is disabled.
• Home Stage: Being the FG generator this engine is, M.U.G.E.N can configure a specific stage with a character of your choice, being attached to one stage in Arcade Mode instead of having a random stage as default. Some characters also include stages alongside them.
• Immune to Flinching: Super Armor, and its permanent Hyper Armor variant, prevents a character from flinching when hit. This can be coded onto a character via the HitOverride function. Note that this usually works for direct attacks and projectiles, reversals that put the character into a flinch state should their attacks make contact still work.
• Interface Screw: Multiple characters are able to disable certain buttons on their enemy's moveset.
• Intra-Franchise Crossover: Commonly seen here, in which you can make the roster as you like, so you can put the same character from different games in the same created fighting game you like.
• Jack of All Stats: Kung Fu Man, the default character that comes with any downloaded copy of M.U.G.E.N (mostly as a coding example and a base for creating characters) and eventually became the mascot of the engine.

M-R

• Mechanically Unusual Fighter:
  • There are lots of these floating around.
  • Most Shoot 'Em Up characters in M.U.G.E.N become this, as they play almost exactly like in their source game.
  • Otherwise normal characters can become this if they are configured to play like this under certain palettes.
• Moveset Clone: Many sprite swaps or sprite edits of another character tend to be these, especially if the movesets aren't changed at all.
• Nigh-Invulnerability: Alot of the characters have either zero hitboxes or seemingly infinite health.
• No Fourth Wall: In general, it's possible to edit winquotes, so any character can play this straight.
• No-Holds-Barred Beatdown: Several melee super arts.
• Nonstandard Character Design:
  • If your roster contains characters from games with wildly different art styles, this is bound to happen.
• Normal Fish in a Tiny Pond: Many platformer characters (both players and bosses) with their original mechanics intact. They tend to have Mercy Invincibility, nullifying combos, and have unblockable attacks that conventional fighters cannot dodge as well as platformer player characters can.
• Not the Fall That Kills You…: Attacks that put the opponent into a falling state can be coded to deal fall damage to an opponent. However, if the falling opponent is hit by another attack that lacks fall damage, it overrides the fall damage and the opponent will not take damage upon hitting the ground.
• One-Hit Kill:
  • Any character that possesses an extremely convenient one to use is almost always considered to be extremely cheap and/or a Lethal Joke Character.
  • The most dangerous one-hit kills come from null spammers and other system exploiters. They do not need to fight you—they can One-Hit Kill you before the match even starts. There is a certain type of system exploiter cheapie that can one-shot the other fighter, the engine itself, and possibly even your computer.
• Overly Long Fighting Animation: Many a One-Hit Kill qualifies for this.
• Perfect Play A.I.: A good number of characters with brutal AI but don't outright cheat tend to have this, being able to block or counter at just the right moments. Some of them even have "command reading", aka their AI can respond to any attack commands the player presses, but otherwise are bound by similar limitations to a player-controlled version of themselves.
• Play as a Boss: Several boss characters have been created for the game, and with the exception of AI-only characters most of them can be selected by the player and controlled just like any other character.
• Power Creep, Power Seep: This tends to happen when creators do not adhere to the idea of converting characters exactly as they were in the source game.
• Pragmatic Adaptation:
  • While most characters are either labelled as accurate but actually aren't, there are a number of characters that are deliberately not meant to be accurate. In some cases, accuracy may not be a good thing.
  • There are also scenarios where a move may have to be reimagined due to engine limitations.
• Press X to Die: The F1 key does this to player 2. For player 1, it's CTRL+F1.
• Purposely Overpowered:
  • Many characters, referred to as "cheap characters" are designed to be as utterly overpowered as possible, packing infinite combos and priority, high-damaging attacks and lightning-quick speed.
  • "Cheapies" are a type of cheap character who take this even further. The weakest of them are Nuke-tier, capable of using fullscreen unblockable instakills while being invulnerable to most forms of attack. Null-tiers (the second-weakest tier) and above are so powerful that can kill their opponent before the match even starts. The main types of characters they're pitted against are other cheapies, usually in a case of cheapie creators constantly trying to one-up each other in a Lensman Arms Race.
  • Certain characters who are otherwise-balanced can come with a palette that gives them cheap abilities if selected. Daniel's 11th palette puts him in unlimited Burst Mode which makes moves that require power drain no power on use.
• Real Men Wear Pink: Since it is easy to customize the colors of the character palettes, it is easy (in most cases) to put even the manliest of men in pink clothes.
• Rule of Fun: This is the only real explanation for the numerous offbeat characters available in the community. Considering how you can pit any character from media against any other character, no other explanation is really needed.

S-Z

• Schizophrenic Difficulty:
  • Characters can be placed at different level orders in Arcade Mode under the "select.def" file. There's nothing stopping the player from placing an SNK Boss as the first opponent, followed by The Sandbag as the second.
  • In addition to Lethal Joke Characters, there are several characters (or at least versions of characters) who are much harder or easier to take on than you might think.
  • In general, characters from older games with extremely different mechanics and pace can have problems with characters from newer games.
• Secret Character: Played With. While the engine by itself doesn't support unlocking characters by fulfilling certain conditions, it's possible to hide characters off-screen in such a way you won't be able to use them unless you know where they are, and some characters have alternate modes you can only access by holding down the taunt button while selecting them.
• Self-Insert: There are quite a number of self-insert characters out there of varying quality, several of which tend to be clones of others.
• Showy Invincible Hero: The players who make M.U.G.E.N videos on YouTube.
  • Most of the intentionally cheap characters that aren't played for laughs focus on Rule of Cool and visual effects instead.
• Sidelined Protagonist Crossover: This occurs whenever a side character gets created before the main character of their series.
• Single Player Gauntlet: A built-in function of the game regardless of setup. You can configure it in an individual build by sorting characters into up to ten order categories in which they can appear, as well as how many characters of each category are to be fought. A simple build might be configured as "1,3,1,2,1,1,0"; in this build, the Order 1 may be a character that is always to be fought first, such as the sample character Kung Fu Man. The three Order 2 characters may be characters with the game's stock AI. The Order 3 character may be a Bonus Stage. The two Order 4 characters may be characters with tougher custom AI built-in. The Order 5 may be a Mini-Boss, and the Order 6 may be a Final Boss. Characters that are never to be encountered such as Joke Characters or Purposely Overpowered characters can either be set to Order 7 here or Order 0 in the select file (which makes them never selected). Characters without an order explicitly set are assumed by the game to be Order 1. Each character may also have an intro and outro cutscene built in, but this depends on whether the character's creator included one, or if you have a generic one configured for anyone who doesn't.
• Situational Sword: It is possible to code attacks that can only hit in certain situations. Some examples: If the opponent is in the hit state ^note Use + on the hit flags; if the opponent is not in the hit state^note Use - on the hit flags; if the opponent has been hit by a certain previous attack ^note Use chainID and set the previous attack's ID to the chainID; and if the opponent was not hit by a certain attack ^note Use noChainID and set the previous attack's ID to the noChainID.
• SNK Boss: Depending on the creator, a character's AI can be written in such a way that any character (even existing SNK Bosses) can turn this trope up to eleven.
• Some Dexterity Required: This tends to occur as a reflection of the source game, although changing the command to something easier is a simple matter of character editing.
• Stylistic Suck: Kung Fu Man's default intro and ending storyboards qualify, as they look like a child's crayon drawings.
• Summon Magic: Some characters do this as a Super Move by calling in a reinforcement to perform an assist.
• Super Not-Drowning Skills: Normally, M.U.G.E.N characters can breathe infinitely in underwater stages.
• Super Special Move: The default character that comes with the game is Kung Fu Man, who plays this straight with his two Hypers. Triple Kung Fu Palm has him perform Kung Fu Palm thrice in succession, while Smash Kung Fu Upper is a much stronger Kung Fu Upper that sends the enemy flying up so high to the point where they take damage when they hit the ground.
• Tag Team: An undocumented code called TagIn allows a character to change their state as well as that of their partner's, but it only functions in WinMUGEN. This can be (and often is) used for a Tag Team function as well as a Switch-Out Move. Third-party tools like UnoTag and Add004 would eventually come in to add in tag-team and assist systems into modern MUGEN setups, but a native tag team mode wouldn't be implemented in the engine itself until IKEMEN.
• Taking You with Me: There are a few instances where characters can take the opponent down with them. In many cases, the one who pulled this off will be considered the victor.
• The Dragon: Kung Fu Man's Evil Doppelgänger serves as this to Suave Dude.
• There Is No Kill Like Overkill: Anything involving lots and lots of blood, characters with lots of flashy effects, and any attacks that reach the 999 combo limit.
• Training Stage: This is one of the two stages that comes pre-packaged with M.U.G.E.N (along with Kung Fu Man's stage), and is often used for character demonstrations due to both the ready availability and the lack of distracting, flashy scenery.
• Ultimate Showdown of Ultimate Destiny: This bears repeating—every fighting game character in history, and then some.
• Unexpected Gameplay Change: It is theoretically possible to import any character from any game, not necessarily fighting games. This trope is the end result if the characters are ported with their source mechanics.
  • Certain bonus stages can be this. One minute you're fighting your opponent; the next, you're playing a rhythm game or platforming.
• Units Not to Scale: The majority of characters based on Kaiju or Humongous Mecha don't take up much more of the screen than normal-size characters, since they're designed to stand alongside other characters of their type (usually due to coming from, or being based off, a fighting game with a roster consisting only of such characters).
• Unskilled, but Strong: Some characters, to make up for not having AI, have inflated attack stats. This can range from a slight damage increase to taking off chunks of your health in a single hit, or even taking you out in a single blow. Many Dragon Ball characters fall under this category.
• Unwinnable Joke Game: Or "Unwinnable Joke A.I. Setting" in this case. There are normally-defeatable characters who have joke AI settings that make them nigh-impossible to defeat.
• Video Game Cruelty Potential: Certain characters can attack or KO their opponents in rather gruesome ways if you activate their special moves, Super Moves or Fatalities.
• Video Game Perversity Potential: Considering how most of the fighters and stages are fan-made content, this was a given. There are many NSFW fighters that have questionable sprites and attacks, and there are stages that have a rather... dirty feel to them.
• Virtual Training Simulation: One of the two stages included in the game is the "Training Room", which is based off other training rooms from other fighting games.
• Weak, but Skilled: Some characters have AI that, while dealing little damage in one attack, can pull off absurdly long combos, in some cases even being able to take the opponent from full health to none without letting them act once. To say nothing of characters with AI that abuses an infinite combo.
• Wolfpack Boss:
  • Several characters are designed to be this.
  • With some luck, you can hack stages to create an odd variant of this.
  • An experienced coder can code this onto any character, making that character attack in a Zerg Rush of easily-defeated clones.
• Would Hurt a Child: Inevitable with child characters available to not only play as, but fight against.
• You Don't Look Like You: This trope comes up whenever a character suffers from shoddy sprite work.

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