Here is the full list of all 27 Kingsway achievements.
The base game contains 21 achievements, and there is 1 DLC pack containing 6 achievements.
Saved the world as the Ascended
Saved the world as the Warrior
Ending #4
Saved the world as the Mage
Ending #2
Highest possible reputation
Saved the world as the Demonblood
Ending #3
Ending #5
Activated all monoliths
Saved the world as the Beastkin
Level 20 Adventurer
Saved the world as the Adventurer
Ending #1
Activated all Guardian Beacons
Level 10 Adventurer
Saved the world as the Rogue
Saved the world as the Worthless
Lowest possible reputation
Saved the world as the Necromancer
Fully upgraded a skill
Learn an ancient spell