Here is the full list of all 57 It came from space, and ate our brains achievements.
Finish the first six levels on medium.
Shoot 95471 times.
Buy all rocketlauncher upgrades.
Kill 7 aliens at once.
Buy all laser upgrades.
Buy all shotgun upgrades.
Finish block ship on any difficulty.
Finish block launchpad on any difficulty.
Reach 75x multiplier.
Finish block scrapyard on any difficulty.
Kill 10000 aliens.
Finish block suburbs on any difficulty.
Finish block industrial on any difficulty.
Finish block navy on any difficulty.
Finish block planet on any difficulty.
Finish the first six levels on easy.
Finish block crash site on any difficulty.
Finish block countryside on any difficulty.
Finish block highway on any difficulty.
Reach 50x multiplier.
Use the shield 5 times.
Buy all machinegun upgrades.
Place 15 mines.
Pick up 100 upgrades dropped by the S.W.A.T. Drone.
Finish block city on any difficulty.
Buy all plasmagun upgrades.
Kill 1338 crawlers.
Place 5 turrets.
Kill 1000 aliens.
Finish block hospital on any difficulty.
Buy all pistol upgrades.
Use the searchlights 5 times.
Reach 25x multiplier.
Kill an enemy close to a player with one health.
Die for the first time.
Died 123 times.
Finish the first six levels on hard.
Finish the first six levels on insane.
Kill 100000 aliens.
Staying alive while other players are waiting to respawn.
Make 25.000.000 amount of Coins in total.
Finish 1 multiplayer game on insane without dying.
Finish 3 multiplayer games on insane without dying.
Finish 6 multiplayer games on insane without dying.
Finish with the highest score in a multiplayer game.
Finish with the highest score in a multiplayer game 10 times.
Revive 5 people using medkits.
Complete all Campaign levels on Easy
Complete all Campaign levels on Medium
Complete all Campaign levels on Hard
Complete all Campaign levels on Insane
Complete Rooftops (Campaign) on any difficulty
Complete Clinic (Campaign) on any difficulty
Complete Alleys (Campaign) on any difficulty
Complete Sewers (Campaign) on any difficulty
Complete Riverside (Campaign) on any difficulty
Complete Cave (Campaign) on any difficulty