The original release included five maps converted from Quake. The gameplay is similar to Quake deathmatch, with essentially the same weapons (except the one for melee combat, which is Half-Life's trademark crowbar instead of the original axe), armour and power-ups. DMC also imitates Quake's physics, which allows an advanced player to gain a lot of extra speed or jump very high by using a number of movement skills such as bunny hopping and rocket jumping.
The default game speed in DMC is somewhat slower than in Quake. The weapons scale from the basic shotgun to the rocket launcher and the "shaft", a powerful directed energy weapon. Three kinds of bonuses are scattered over the maps, which give the player a temporary special power: "quad damage", "invulnerability", and the "ring of shadows" which turns the player into a ghostly, almost invisible figure.