Chaos Break is essentially a third-person shooting game, with echoes of survival horror such as Resident Evil. Set in an abandoned biochemical laboratory on an isolated island, the two player characters, Mitsuki and Rick, are part of an investigatory and cleansing force sent to find out the cause of an 'anomalous thermal reaction'. This game is a spin-off, set in the same universe as the arcade game Chaos Heat.

Progress through the game is made by defeating enemies, which in this case are alien lifeforms and the laboratory's own automated defence system. An element of survival horror is introduced through the use of computer terminals, where the player can save and read files explaining the backstory of the game.