Monster Madness: Grave Danger is a reworking of Monster Madness: Battle for Suburbia. As in that game, players take control of one of four teenagers that have to defend their suburban town from a zombie invasion.
While the main adventure mode stages remain the same from the earlier game, this version allows players to tackle the main adventure mode cooperatively online.
A challenge mode has also been added which is a set of 25 minigames, which include a home-run contest, guiding a fairground swan down a river, and a Concentration type card game. Beating these challenges unlocks extra character costumes.
Other changes include the controls being overhauled to a more conventional dual-stick shooter control scheme. Also, this game does away with the previous game's checkpoint system, and replaces it with a respawn system in which each death just costs the player monster tokens. There is also the addition of 100 character-specific purchasable accessories.