Here is the full list of all 88 I am not a Monster: First Contact achievements.
Complete "Ambush"
Remove infection 3 times
Win 20 battles
Deal 1,000 damage with melee weapons
Use heroic ability 5 times
Get "Cruelty" trophy in the game
Kill 10 enemies
Get "Rescuer" trophy in the game
Save 10 civilians
Get "Soldier" trophy in the game
Deal 100 damage with explosives
Recover 100 HP
Deal 100 damage with melee weapons
Infect 5 humans
Win for the monsters without dying
Win 5 battles
Deal 100 damage with bullet weapons
End the battle without getting Guilt
Win for the humans without dying
Deal 100 damage with energy weapons
Recover 1,000 HP
Recover 10,000 HP
Deal 5,000 damage with bullet weapons
Deal 50,000 damage with bullet weapons
Deal 5,000 damage with energy weapons
Deal 50,000 damage with energy weapons
Deal 5,000 damage with explosives
Deal 50,000 damage with explosives
Deal 5,000 damage with melee weapons
Fill the morale bar 10 times
Infect 100 humans
Infect 500 humans
Kill 100 enemies
Kill 1,000 enemies
Save 100 civilians
Save 1,000 civilians
Turn a hero into a monster
Win 500 battles
Get "Hero Certificate" 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
Complete "Creature From Space"
Complete "Laser’s Fist"
Complete "Lead Role"
Complete "An Otherworldly Hangover"
Complete "Last Dance"
Complete "Technicalities"
Complete "Welcome!"
Complete "Deadly Party"
Complete "You're Fired!"
Complete "On Tiptoes"
Complete "Diamond Tears"
Complete "Massacre"
Complete "Transformation"
Complete "Betrayal"
Complete "Black Sheep"
Complete "Call of the Sky"
Complete "Whose Shuttle is This?"
Complete "Death to Earthlings"
Complete "We're Family"
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"