Kirby is the titular character and main protagonist of the video game series of the same name. It is unknown how old Kirby is, but it is implied that he is either a baby or a young child, or at the very least, has the mind of one.
While it is unknown where Kirby originated from, he has resided on Planet Popstar in the kingdom of Dream Land for the majority of his life. He is a small pink puffball with short, stubby arms and large feet His main ability is that of inhaling his opponents and gaining their abilities in the process. Kirby has also appeared in all entries of the Super Smash Bros. series.
In M.U.G.E.N, there are various versions of Kirby, but the most well-known is Bane84's version, most likely due to it being able to change M.U.G.E.N's core gameplay into that of Super Smash Bros.'s when fighting against itself and characters that use the same base code.
Stated to be incomplete, this Kirby plays similarly to characters from the Marvel vs. Capcom series, complete with a Launcher and Super Jump. Perhaps it inhaled Tedhaun before the match, but Kirby occasionally comes back to life during simul mode, but only for short periods of time.
This version of Kirby has sprites that are from Kirby Super Star and is a six-button character. Kirby's attacks are based on the many copy abilities from said game. This Kirby can be hard to beat due to its brutal A.I. and small size. Its K.O. animation has him falling off of the screen, like in the source game. Strangely, its taunts are activated by pressing multiple buttons, and not just Start. It also comes in a .dgc file, so when you download him, you'll need to download a .dgc file extractor to extract him.
This version of Kirby was made by Cyanide and is based on its appearance in Kirby & The Amazing Mirror. Some of its attacks are based on the source game and is considered as a very easy character to play as. It is also rather small, making it difficult to hit.
This Kirby is based on its appearance in Super Smash Bros. Brawl and has coding specifically for a Smash Bros.-styled M.U.G.E.N match. The only stage available is Final Destination, but Bane84 said he would make more characters and stages for it. Karter's Mario is also compatible with this Kirby.
Madoldcrow1105's Kirby, like its other characters, are only compatible with M.U.G.E.N 1.0. The character has red outlines and, unlike its other characters, it does not have an original palette. Madoldcrow's Kirby actually plays in a SNK-esque style of gameplay, which is different to the other Kirby characters available beforehand. This Kirby can also use some copy abilities. Some of its commands do not seem to work, specifically its Hypers. Its A.I. is very easy and no challenge at all.
Seku's Kirby uses hi-res (D4) sprites, and may play as the most complicated of them all. It has a meter showing how many times it can puff up in midair (up to 5 times) and has various attacks from Kirby's Return to Dreamland, Super Smash Bros., Kirby 64: The Crystal Shards, and Kirby Air Ride. It can switch attack modes by eating its foe, but the meter (mentioned above) could cause M.U.G.E.N to lag.
On Seku's OneDrive account, Kirby is the second and third file in the "MUGEN公開キャラ" folder. As of now, the current version (ver 2.01) seems to be offline. It also blocks like in Smash Bros. meaning that it can't block for too long, and can't in mid air. Its A.I. is very easy, but there is an A.I. patch for him.
This particular Kirby uses sprites from Kirby Mass Attack (more specifically, one of its minigames, Kirby Quest). It also uses the game's common enemies as strikers. Its A.I. will spam its strikers and powerful attacks, making it difficult to take down with a slow, bulky character, or a character without projectiles. The most recent update has different Hyper portraits, fixed glitches, and new A.I., meaning it won't spam helpers, but instead Hypers. Super Nicholas is trying to make this Kirby invulnerable to characters such as Slime.
This Kirby is unique because it can switch copy abilities in battle, similarly to how Kirby can in the Milky Way Wishes sub-game of Kirby Super Star and its remake. It also uses a separate button to block.
MUGENX also made a NES Kirby. Like everything else of his, it plays completely like a Smash Bros. character and it is very cheap. Like its Smash Bros. counterpart, Kirby is able to inhale certain characters to gain access to additional moves.
There is also a Kirby that has poorly ripped sprites from the Super Smash Bros. Brawl trailer. There is a large collection of these characters available. Unfortunately, they are all poor quality, in terms of sprites, sounds, and attacks.
This Kirby, or Momo Kirby, has a sword. It plays similar to the Kirby games, as having a button to jump and block. It has several attacks, along the lines of slashing at the opponent. It is available on his website.
Project64Mugen made a Kirby named Custom Kirby, who plays like a mix between Bird's and Xex's Kirby. It has Super Star-themed sprites, but slightly edited. It doesn't seem to be on the creator's site, making him very rare. This Kirby carries different Hypers, but aside from that, isn't very different from Bird's Kirby.
There is also another Kirby, similar to MUGENX's that uses Kirby's Adventure sprites, except it has most of its abilities. This may be the only Kirby that uses its animal friends from Kirby's Dream Land. It also has EX Specials. Strangely, It uses Kim Kaphwan in a Hyper Combo. This Kirby is also very small, giving larger characters an exceptionally big disadvantage.