Here is the full list of all 50 Planescape: Torment: Enhanced Edition achievements.
Reach level 12 in Mage class before any other class.
Train to become a Mage.
Reach Good Alignment (any).
Gained Dak'kon as a companion.
Advance an attribute score to 25.
Escaped the Mortuary.
Switch back to Fighter class over the course of the game.
Train to become a Thief.
Reach level 12 in Fighter class before any other class.
Reach level 12 in Thief class before any other class.
Reach Chaotic Alignment (any).
Reach Lawful Alignment (any).
Reach Evil Alignment (any).
Maintained True Neutral Alignment until the end of the game.
Drew the Lady's Gaze and got mazed.
Escaped the Lady's Maze - this time.
Gave birth to Adahn through belief.
Defeated the Modron Wizard.
Join Anarchists.
Join Dustmen.
Join Sensates.
Join Xaositects.
Rescued Morte.
Gained Annah as a companion.
Gained Fall-From-Grace as a companion.
Gained Vhailor as a companion.
Gained Ignus as a companion.
Gained Nordom as a companion.
Discovered the truth of why Morte is with you.
Discovered your connection to Ignus.
Helped Nordom resolve his issues.
Advanced Dak'kon's karach blade to highest neutral point.
Advanced Dak'kon's karach blade to highest evil point.
Advanced Dak'kon's karach blade to highest honor point.
Issued Pronouncement of Two Deaths of One at Fortress of Regrets.
Discovered why Dak'kon's faith is shattered.
Restored Dak'kon's faith.
Returned to Mebbeth and restored Unity of Rings.
Dealt with Ravel Puzzlewell.
Met all of Ravel's branching incarnations in Sigil.
Shifted Curst back to the Outlands.
Dealt with Trias the Betrayer.
Found Pharod's Vault. It smells in there.
Recovered the Bronze Sphere.
Your name, at last.
Entered the Fortress of Regrets on your own.
Kill all 3 incarnations in Fortress of Regrets.
Absorb all 3 incarnations in the Fortress of Regrets.
Defeated your adversary.
Gave the Transcendent One an answer to a "meaningless question."