Here is the full list of all 66 Alien Swarm achievements.
Awarded for finishing the Jacob campaign on Brutal difficulty.
Complete any mission on Brutal difficulty with Onslaught and Hardcore Friendly Fire enabled.
Kill 100,000 Swarm.
Heal 300 points of damage in a single mission without dealing any non-melee damage to the Swarm.
Complete Timor Station within 4:25 on Normal difficulty or harder without any marines dying.
Kill 15 Swarm with all four marines under the effects of a Damage Amp in a single mission.
Kill 25,000 Swarm.
Kill 100 Swarm with Laser Tripmines.
Complete SynTek Residential within 2:30 on Normal difficulty or harder without any marines dying.
Complete Cargo Elevator within 2:50 on Normal difficulty or harder without any marines dying.
Complete Landing Bay within 1:25 on Normal difficulty or harder without any marines dying.
Complete Deima Surface Bridge within 2:30 on Normal difficulty or harder without any marines dying.
Complete Sewer Junction within 1:30 on Normal difficulty or harder without any marines dying.
Kill 100 Swarm with Incendiary Mines.
Kill 250 Swarm with a Grenade Launcher.
Kill 250 Swarm with a Marksman Rifle.
Kill 6 Swarm with a single Grenade.
Awarded for finishing the Jacob campaign on Insane difficulty.
Complete a campaign on Normal difficulty or harder without any marines dying.
Complete 10 computer hacks without access being logged.
Kill 250 Swarm with a Rail Rifle.
Kill 250 Swarm with Twin Pistols.
Kill 250 Swarm with a Minigun.
Kill 250 Swarm with a Shotgun.
Kill a Swarm Parasite with a melee attack.
Kill 250 Swarm with PDWs.
Stun 6 Swarm with a single Stun Grenade.
Complete Rydberg Reactor within 3:10 on Normal difficulty or harder without any marines dying.
Kill 100 Swarm with Hornet Barrages.
Complete 10 wire hacks without access being logged.
Complete the Jacob's Rest campaign on Hard difficulty or harder.
Deploy 10 ammo stashes that are used by other marines.
Freeze 6 Swarm with a single Freeze Grenade.
Kill 250 Swarm with a Vindicator.
Kill 250 Swarm with a Chainsaw.
Kill 5,000 Swarm.
Kill 250 Swarm with the Assault Rifle.
Kill 250 Swarm with a Tesla Cannon.
Heal all 4 marines with a single Heal Beacon.
Kill 500 Swarm with deployable Sentry Guns.
Complete the Jacob's Rest campaign on Easy difficulty or harder.
Complete the Jacob's Rest campaign on Normal difficulty or harder.
Kill 250 Swarm with a Prototype Rifle.
Unlock all the available weapons.
Destroy all Swarm Eggs in a mission without allowing any to hatch.
Cure an Infested marine.
Kill 20 Swarm with melee attacks in a single mission.
Kill 250 Swarm with a Flamethrower.
Kill 5 Swarm with explosive barrels in a single mission.
Kill 100 Swarm Grubs.
Successfully perform 5 fast reloads in a row.
Kill 1,000 Swarm.
Deliver the finishing blow to a Swarm Shieldbug.
Roll under a Swarm Ranger projectile.
Complete a mission with no friendly fire incidents. Four marines must be present in the mission.
Complete a mission with better than 90% accuracy.
Kill 25 drones without friendly fire. Four marines must be present in the mission.
Kill 250 Swarm with an Autogun.
Complete 2 co-op missions online. Earns a Team Fortress 2 parasite hat.
Complete a mission on Normal difficulty or harder without receiving any damage.
Finish a mission without the tech getting killed.
Complete a mission on Normal difficulty or harder without any marines dying.
Guard the squad's tech so that he takes no damage during the hack.
Successfully perform a fast reload.
Seal a door with the welder.
Kill a Swarm Boomer before it inflates.