Here is the full list of all 49 Alien Rage - Unlimited achievements. It takes around 20-25 hours to unlock all of the achievements on Windows.
500 Kills With Explosions
Complete single player campaign on Brutal difficulty
Complete single player campaign on all difficulty levels
25 Kills Using Mech To Step On Enemies
Complete single player campaign on Hard difficulty
80 Kills While Piloting Mech
1000 Promethium Containers Destroyed
Reach a player score of 50,000,000
500 Total Headshots
1500 Total Kills
Complete single player campaign on any difficulty level
Complete single player campaign on Normal difficulty
Play entire campaign using only the pistol
Play entire campaign using only 1 weapon
Defeat Vorus God Mech
Defeat all Bosses
Defeat DF9 Sentry Mech
Unlock all player perks
Find all audio recordings
Destroy the security control room
250 Kills With Melee
Kill an enemy with every weapon
Use every weapon’s secondary fire mode
Use all weapons
Find all weapons
Defeat Vorus Primus
Set the docking tower centrifuge to overdrive
Reach a player score of 25,000,000
Defeat GX-7 Destroyer Prototype
Defeat AA-19 Combat Mech
Defeat Mk XII Heavy Mech
Defeat Vorus Gladiator
Survive the Heavy room
Defeat Security Turrets
Take out the bunker
Defeat Vorus Centurion
Unlock first Perk
Lower the bridge
Find a new weapon
Find an alien weapon
Use any weapon’s secondary fire mode
Win 10 multiplayer games
Play as an alien in a multiplayer game
Completely recover from damage 3 times during a multiplayer match
Get the most kills during a single multiplayer match
Get the most kills AND never die during a single multiplayer match
Play as a human in a multiplayer game
Never die during a single multiplayer match
Join a multiplayer game