King of the Monsters is an action/fighting game that features city-destroying battles between huge monsters. Choose one of six monsters and travel around Japan, stopping to fight in various famous cities, with the aim of becoming the ultimate winner. In addition to punches, kicks, and other regular moves, each character has the ability to use more devastating maneuvers, like throwing flames and shooting laser beams, to defeat opponents. Wrestling elements are also incorporated, as you must completely exhaust your opponent and get a three-count to pin him and be victorious.
Players choose one of six monsters (four in the 16-bit ports) for battle, and two players can join forces to fight the monsters together. Battles end when one of the monsters is pinned for a three count or if time expires (in which case the player loses). The game consists of 12 total levels (8 in the 16-bit ports) which takes place in 6 cities in a futuristic 1996 Japan. Each city is featured twice with the game beginning and ending in Tokyo.