Remember, kids. Friendly fire - isn't.


Friendly fire describes any damage done by a player that injures a teammate. Aside from the obvious end result of bringing your squad members closer to death, friendly fire usually is a waste of ammunition. During sessions at a higher difficulty, ammo conservation is crucial, so friendly fire should be avoided to make sure that more rounds get sent into swarm as opposed to squad mates.

How it worksEdit

Friendly fire is managed by an absorption system. Depending on the difficulty level, a marine will absorb a portion of the incoming friendly fire damage. As the marine is hit by more friendly fire, the amount of damage that is absorbed will decrease so the overall damage taken will increase. This absorption amount will recover over time provided the marine doesn't become a victim of additional friendly fire. The end result is that occasional friendly fire incidents won't destroy your squad, but sustained friendly fire will eventually result in death.

Minimizing friendly fireEdit

  • Players should position themselves so that they do not block each other's line of fire. This requires some communication between squad members as well as common sense.
  • One of the easiest ways to avoid friendly fire when on the move is to hug the walls. If two marines are walking down a corridor, each on their own side, the risks of friendly fire are close to zero, as they can both fire down the corridor or behind themselves safely.
  • When setting up defenses, pick a spot and stick to defending that area. Moving around as aliens attack from multiple sides always results in friendly fire, which may tip the scales, so trust your squad mates to cover their own area.
  • Do not get greedy or reckless for kills; play it safe, play it smart. You're supposed to kill the swarm, not use your body to shield them from your fellow marines's fire.
  • When attempting to kill swarm in close quarters to a squad mate, if possible, kill with melee strikes or Tesla weaponry. Neither of these can inflict friendly fire damage. However, these methods can be ineffective in dispatching swarm quickly, rendering them less useful for dispatching mobs of swarm in close quarters to a squad member.
  • Three very important words you should remember: Short. Controlled. Bursts. Spraying bullets around with wild abandon may be fun, but doing so makes it very likely that someone will step in the way of a bullet, or five of them. Not only does using shorter bursts of fire conserve ammunition, it also makes it less likely you'll shoot a fellow marine - and it limits how much damage that friendly fire incident can do, too.

Hardcore Friendly FireEdit

Main article: Difficulty

"Hardcore Friendly Fire, means that friendly fire deals full damage immediately, Flamers set teammates on fire much faster, and sentry guns will hurt you if get caught in their crossfire.

Full friendly fireEdit

Alien Swarm 2K4Edit

Crouched players are still prone to friendly fire.

Alien Swarm SourceEdit

Veterans of Alien Swarm 2K4 might notice that friendly fire is severely reduced when compared to the original or to the damage it deals to the aliens. In order to play with full friendly fire, add this line to your autoexec.cfg:

mp_friendlyfire 1
asw_marine_ff_absorption 0

Friendly fire commandsEdit

Currently, the following console commands work if sv_cheats is set to 1 (therefore, no experience points will be granted to you after a multiplayer match).

  • asw_marine_ff 0 (weapon lock/anti TK Guard mode[!!!]) or 1 (default; Guard off)
  • asw_marine_ff_guard_time 5.0 (Weapon lock time in seconds; default value. Set to desired duration, or make it indefinite for Moses.)
  • asw_sentry_friendly_fire_scale 1 (Sentries damage and kill players who get in the way)
  • asw_weapon_safety_hull 0 (Default; dictates how willing AI is to shoot you to get at Swarm. May or may not make Sentries decide to not kill you if you're in the way, a very valuable fix for the Flamer Sentry if so. Play with the numbers and post your results!)
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