01Achievements
Every Alien Swarm achievement, ordered by how few players in the world have unlocked it.
2 of 66 entries
Hat TrickComplete 2 co-op missions online. Earns a Team Fortress 2 parasite hat.55.2%Common
Technician SecuredFinish a mission without the tech getting killed.55.7%Common
Data from Steam — Steam Web API Terms of Use. Last updated .