- "Outgoing Stim Grenade."
- —Damon Baird, throwing a Stim-Gas Grenade
The Stim-Gas Grenade, or Stim Grenade, is a healing grenade that releases a blue cloud of gas called Stim, that has the ability to heal or revive teammates for a short period of time. Only gibbing attacks, such as Frag Grenades and close range shotgun kills, or headshots will kill a player standing in the stim cloud.
In the multiplayer modes OverRun and Survival, the COG Medic class has a Stim-Gas Grenade as its special ability, and as such, it must recharge after each use. Injured allies can be healed and any ally that was killed with a non-gib attack can be revived by throwing a stim grenade near them. Keep in mind that dead allies automatically respawn after 10 seconds if not revived.
In other Versus modes that allow stim grenades, the gas cloud dissipates much earlier than in campaign or OverRun/Survival. Also, a stim grenade thrown by a player on the red team will release a red cloud, making it easy to differentiate between friendly and enemy stim gas.