Here is the full list of all 88 I am not a Monster: First Contact achievements.
Complete "Death to Earthlings"
Complete "Whose Shuttle is This?"
Complete "We're Family"
Complete "Black Sheep"
Complete "Call of the Sky"
Complete "Ambush"
Complete "Betrayal"
Complete "Transformation"
Complete "Massacre"
Complete "Diamond Tears"
Complete "On Tiptoes"
Complete "You're Fired!"
Complete "Deadly Party"
Complete "Welcome!"
Complete "Technicalities"
Complete "Last Dance"
Complete "An Otherworldly Hangover"
Complete "Lead Role"
Complete "Laser’s Fist"
Complete "Creature From Space"
Recover 100 HP
Recover 1,000 HP
Recover 10,000 HP
Deal 100 damage with bullet weapons
Deal 5,000 damage with bullet weapons
Deal 50,000 damage with bullet weapons
Deal 100 damage with energy weapons
Deal 5,000 damage with energy weapons
Deal 50,000 damage with energy weapons
Deal 100 damage with explosives
Deal 5,000 damage with explosives
Deal 50,000 damage with explosives
Deal 100 damage with melee weapons
Deal 1,000 damage with melee weapons
Deal 5,000 damage with melee weapons
Remove infection 3 times
Fill the morale bar 10 times
Infect 5 humans
Infect 100 humans
Infect 500 humans
Kill 10 enemies
Kill 100 enemies
Kill 1,000 enemies
End the battle without getting Guilt
Save 10 civilians
Save 100 civilians
Save 1,000 civilians
Turn a hero into a monster
Use heroic ability 5 times
Win 5 battles
Win 20 battles
Win 500 battles
Win for the humans without dying
Win for the monsters without dying
Get "Hero Certificate" trophy in the game
Get "Cruelty" trophy in the game
Get "General" trophy in the game
Get "Hero In Action" trophy in the game
Get "Space Legend" trophy in the game
Get "Monster Mastery" trophy in the game
Get "Ruthless" trophy in the game
Get "Beast" trophy in the game
Get "Officer" trophy in the game
Get "Perfect Hero" trophy in the game
Get "Rescuer" trophy in the game
Get "Soldier" trophy in the game
Complete "Plan B"
Complete "Fresh Air"
Complete "Do Not Touch!"
Complete "Do Not Feed the Animals!"
Complete "Sisyphean Task"
Complete "The Belly of the Beast"
Complete "Indestructible"
Complete "Revelation"
Complete "Escape"
Complete "Laser Power"
Complete "Metro"
Complete "Stubbornness"
Complete "Vicious Circle"
Complete "New Hope"
Complete "Phoenix"
Complete "Magician"
Complete "Dark Side"
Complete "Light in the Dark"
Complete "Mr. X"
Complete "Old School"
Complete "Sector 17"
Complete "Portal"