Heaven's Gate is a 3D fighting game with an arcade and Vs. mode. The player can choose from one of the eight combatants that are available at the start, with a few more characters being available once their unlocked. Each character has a different nationality, specialty, and lineage. Each character represents either a good or an evil alignment and depending on the character chosen, it affects which final boss the player will have to fight against.

Defending, punching and kicking are on three separate buttons. There are variations of each of these moves depending on how quick the button is pressed.

Consistently damaging or taking damage from an opponent will add to a sol or lunar (depending on the character the player is playing as) power gauge. When this gauge is filled, the player is temporarily invincible and allows the player to use strong power assault moves.