Here is the full list of all 54 Chronicles of a Dark Lord: Episode II War of The Abyss achievements.
Defeated Xe'on
Completed the Prologue
Completed Chapter 1
Completed Chapter 2
Completed Chapter 3
Completed Chapter 4
Completed Chapter 5
Completed Chapter 6
Retrieved the blood of the Revenoth
Destroyed all 5 Teleporters
Defeated Appolly'ione
Repelled the invasion of Ilian
Destroyed the first Nexus Tower
Destroyed the final Nexus Tower
Defeated Urolus
Defeated Xesis
Completed the game
Transform Serena into a bunny
Confine Serena in the Dungeons
Kill Serena
View the Scion Grid Tutorial
Viewed all of the past events in the Mirror Room
Found Gelina's portrait
Kill Lars
Used Lars as a means of execution
Killed every enemy on the Kisareth-Ilian Bridge
Destroyed a teddy bear
Informed Tia about her husband's fate
Killed a woman in Ilian Castle
Froze a woman in Ilian Castle
Miniaturized a woman in Ilian Castle
Found Shanora's Keepsake
Killed a woman in Starfall
Allowed Zexor to live
Executed Zexor for his crimes
Found Diovol's weakness
Win at least 20 battles on Solara Bridge
Found the way to the Inferni Diadem
Defeated Shade of Exodes
Killed Milton
Upgraded Riggs or Jesiah to Level 10
Completed Magus' Scion Grid
Completed the Arena
Completed the Infernus Ruins area
Recruited Eriadne
Defeated the Phaelyrm
Found a Level 10 Wisdom Scion at the Garlan Mountains
Found the Skull of Onyus at the Garlan Mountains
Defeated She'dai
Defeated John Sierra
Defeated Erovoxis
Visited Trinity in the Healer's Ward
Found the Developer's Room
View an alternate game over ending