X-Men: Children of the Atom is a 2D superhero fighting game developed and released by Capcom for arcades (running their CPS-2 hardware). It was first released in Japan on December 17, 1994 and then released worldwide on January 5, 1995.
While it is their third game under partnership with Marvel Comics (after The Punisher and X-Men: Mutant Apocalypse), it is their first fighting game (and the first fighting game overall) set in the Marvel universe. It uses a fast-paced gameplay engine and cartoonish visual style, both based on their previous game, Darkstalkers: The Night Warriors.
Set during the Fatal Attractions crossover story arc in the various X-Men comics, the game pits the titular mutant team against the forces of Magneto (who plans to use his space station Avalon to conquer humanity).
The game was originally ported to the Sega Saturn as a console exclusive, released first in Japan (on November 22, 1995, published by Capcom), and then worldwide (in April 1996, published by Acclaim). It was later ported by Probe to the PC (in May 1997) and Sony PlayStation (in February 1998), both published by Acclaim and both only released outside of Japan. All ports include cheat codes that allow players to play as the boss characters.
X-Men: Children of the Atom received two sequels: Marvel Super Heroes (bringing heroes and villains from other groups in the Marvel universe) and X-Men vs. Street Fighter (a tag-team crossover with the Street Fighter Alpha series). Its gameplay was expanded, adding new techniques and gameplay mechanics, while the latter sequel spawned a long-running series (known as Marvel vs. Capcom).
Each player has an "X-Power" gauge similar to that of Super Street Fighter II Turbo as well as the "Special" gauge in Darkstalkers. The "X-Power" gauge builds up as the player performs moves during a match and has two levels, in which the player can then perform "X-Ability" which uses a smaller amount of the gauge and the "Hyper-X" which uses a lot more of the power gauge. Also, countering throws will also drain some of your power gauge.
X-Men Children of the Atom also introduces to fighting games, the ability to do super jumps, roll toward or away from an opponent after a throw to perform more attacks, and also being able to determine projectile attacks, such as Cyclops' Eye Beam. As well the player can choose between manual or automatic blocking, but some in game features will not be available if the player chooses automatic.
The game includes 10 playable fighters, 2 unplayable bosses, and one secret guest opponent. All characters (other than the secret guest opponent) are voiced by their voice actors from the X-Men animated series.