Full list of all 43 Immortal: Unchained achievements.
The base game contains 31 achievements, and there are 3 DLC packs containing 12 achievements.
Survived the attack on the Great Hall
After connecting the third nexus point
Kill 100 enemies with the quick melee
After connecting the second nexus point
Kill 100 enemies with a SMG
Kill 100 enemies with a Shotgun
Kill 100 enemies with an Assault Rifle
Decypher an item
After connecting the first nexus point
Find an armour shrine
Connect with the Monolith
Kill 100 enemies with a Pistol
Kill 100 enemies with a Sniper Rifle
Die from one of your own attacks
Upgrade one of your weapons
Get all achievements
Kill Malog. The raging storm
Kill Arlen. The corruptor
Kill Iska. Queen of the Abyss
Enter Naylon World
Complete the Game
Upgrade a weapon to the highest level!
Find all armour shrines
Equip a fully upgraded weapon in each weapon slot
Find all Lore Items
Kill 100 enemies with a Launcher
Kill 100 enemies while attacking them in the back
Finish The Pilgrim's Pilgrimage questline
Finish The Lost Hunter Found questline
Finish the Lost Memories questline
Recover 10000 or more bits from one death
Get cursed while playing as The Cursed One
Finish a normal playthrough as The Cursed One
Get all curses while playing as The Cursed One
Complete New Game+
Complete New Game++
Complete New Game+++
Complete New Game++++
Kill 100 enemies with a lightning blaster
Finish the Nayra questline
Collect all lore items in Storm Breaker