Here is the full list of all 55 Xenomarine achievements.
Kill 100 enemies in a roguelike game
Kill 1000 enemies in a roguelike game
Kill 1 enemy
Kill 5 enemies with 1 attack
Kill 10 enemies with 1 attack
Kill 100 enemies in close combat in a roguelike game
Kill 1000 enemies in close combat in a roguelike game
Complete level 1
Complete level 10
Complete level 50
Walk 1000 tiles in a roguelike game
Walk 10,000 tiles in a roguelike game
Gain 5 skill levels
Gain 10 skill levels
Gain 50 skill levels
Become a Master Xenomarine
Become a Heavy Weapons Expert
Become a Ninja Master
Become a Master Mechanic
Become a Special Ops Expert
Craft 10 items in a roguelike game
Improve a weapon
Improve a piece of armor
Destroy an alien egg
Destroy a crate
Spot a secret door
Use mind control on 5 aliens in a roguelike game
Successfully hack 5 drones in a roguelike game
Kill an enemy with a turret
Hack a turret
Kill an enemy at range 10 with a rifle
Use night vision for 10 turns
Use a singularity globe
Set a trap
Destroy a wall
Destroy a hidden secret door
Use an AI power enhancer on a weapon
Improve a weapon to 100% accuracy
Kill (at least one of) all alien types of the same colour
Kill at least one of every species of facehugger
Kill at least one of every alien species
Complete a security mission
Use a jetpack
Use a medkit at 1 health
Gain +5 hit for 3 separate species
Equip superheavy armor
Ascend to higher dimensions
Equip a 7 slot equipment belt
Kill an enemy using a mindcontrolled enemy
Reach level 10 in a adventure mode game
Reach level 50 in an adventure mode game
achieve 100% resistance for at least 3 resistance types
Achieve at least 50% resistance for all resistance types
Complete a level in under a minute
Complete 10 levels in under 30 minutes