Ultraman is a character who appears in the Ultra Series, a series of extremely popular television programs in Japan which began airing in the mid-1960's, and continue on to this day. Ultraman is the first Ultra to appear in the series, and made his debut in the second Ultra Series show, simply titled Ultraman.
In M.U.G.E.N, Ultraman has been made by kuma and Muu. Kuma's version is giant Apocalypse-style character intended to be a boss, aptly named 'Giant Ultraman', whereas Muu's version is a more traditional character.
Unlike kuma's Ultraman(Giant Ultraman), which is designed as a boss-like character, this version is designed to be more of a traditional character. He had balanced AI and a variety of specials, and is also a very reliable character, just like Muu's other characters. This is the most popular version of the hero in the M.U.G.E.N. universe.
Giant Ultraman is an Apocalypse-sized boss character that takes up nearly half of the screen. Giant Ultraman can be quite annoying to fight against, utilising attacks with great range such as its slapping attacks and shockwaves, the former of which it will use frequently when an invisible wall is on-screen, constantly bouncing the opponent between the wall and its slapping attacks for easy combos that rack up heavy damage. Its most powerful move is called Specium Ray, a powerful beam that can deal a lot of damage if the opponent is unlucky enough to get caught in it.