Deathmatch Combat io is a fast-paced 3D first-person shooter with game modes such as zombie survival, arcade, deathmatch, team deathmatch, battle royale, and doom royale. It also allows for the addition of bots in the room and has five maps with power-ups like regeneration, damage, unlimited dash, and shield. Players can choose from 11 weapons and access weapon skins through a level system. There are also options for armor and mask customization, as well as long distance markers in deathmatch and team deathmatch mode.