Here is the full list of all 86 Earthfall achievements.
Kill 300 Threshers
Kill 60 Beasts
Killed 9999999 Blackouts
Kill 80 Whiplashes
Kill 2500 aliens with melee weapons
Complete the Hatchery mission on Overwhelming difficulty
Kill 15 Beasts
Complete the Revelation mission on Overwhelming difficulty
Complete the Hatchery Finale mission on Overwhelming difficulty
Complete the Dam mission on Overwhelming difficulty
Kill 1500 aliens with the Combat CVA
Kill 1500 aliens with the EF18
Complete the Warehouse mission on Overwhelming difficulty
Killed 99999 Blackouts
Finished any campaign on the hardest difficulty
Complete the Sunnyvale mission on Overwhelming difficulty
Kill 1000 aliens with the AK47
Complete the Data Recovery mission on Overwhelming difficulty
Kill 180 Sappers
Kill 20 Whiplashes
Complete the Supply Run mission on Overwhelming difficulty
Complete the Radio Silence mission on Overwhelming difficulty
Kill 750 aliens with the Vendetta
Killed 50 consecutive aliens with headshots or brainshots
Complete the Breakdown mission on Overwhelming diffculty
Save 40 unconscious players
Kill 700 aliens with a melee weapon
Kill 1000 aliens with the Valkyrie
Kill 5 Beasts
Save 40 pinned players
Kill 10 Whiplashes
Kill 600 or more Drones by shooting them through the brain
Kill 75 Threshers
Heal 60 players
Kill 750 aliens with the Glintec
Kill 1000 aliens with the MP5
Save 40 incapacitated players
Kill 1000 aliens with the Berg 930
Kill 8000 Drones
Kill 1000 aliens with the AK67
Deployed 100 Barrier Kits
Kill 1000 aliens with the Reaper
Kill 1000 aliens with the Harbinger
Heal 20 players
Kill 35 Threshers
Shove a Thresher out of the air
Kill 500 aliens with the SW22
Complete all missions in the Natural Selection campaign
Complete the Hatchery Finale Center mission
Deploy 25 mounted guns
Kill 45 Sappers
Complete the Hatchery Center mission
Kill 600 aliens with headshots
Complete the Dam mission
Kill 999 Blackouts
Kill 150 aliens with grenades
Complete the Warehouse mission
Kill a Sapper with fire
Kill 20 Sappers
Complete all missions in the Invasive Species campaign
Complete the Radio Silence mission
Kill 400 aliens with a Mounted Gun
Complete the Sunnyvale mission
Complete the Data Recovery mission
Complete the Breakdown mission
Complete the Supply Run mission
Win a game with high accuracy
Make it through a mission without being incapacitated
Use a health item on another player
Complete the Revelation mission
Shove a Sapper
Kill 2000 Drones
Kill 1000 Drones
Killed 5 aliens with one shot
Kill 10 Enragers
Initiate a print on a 3D Printer
Killed 25 aliens in 1 minute or less
Deploy a Mounted Gun
Rescue someone from the Whiplash
Restore power to a printer or health station
Completed a mission using only pistols
Help an incapacitated player up
Rescue someone pinned by the Thresher
Kill an alien with a melee weapon
Use a health item on yourself
Deploy a Barrier Kit