The COG One-Shot heavy-class sniper rifle/recoiless rifle can obliterate an enemy with a single round. The rifle also has the capability to shoot right through a Boomshield, stunning the enemy holding the shield in the process. While the rifle always delivers an instant kill, it is very slow to reload between shots. Every new round must also be charged up for a few seconds by aiming the weapon, all the while exposing the weapon's laser sight to all players.
Along with the Locust-engineered Mortar and Mulcher, the One-Shot is classified as a "heavy weapon" and its spawn point can often become hotly contested on multiplayer maps.
- The insignia on the rifle is an elephant. This is because Epic Games designers love to jokingly refer to the gun as the "elephant gun".