This achievement is gained upon defeating the following rare monsters found in the level 65+ hard difficulty adventures in Mistmoore's Catacombs: Dreary Grotto:

Despairing Trueborn Soul
Dishonored Trueborn Spirit
Malicious Scion Shadow
Malicious Trueborn Essence
Scion Assassin
Scion Bone Binder
Scion Brutish Converter
Scion Captain
Scion Deathmender
Scion Dismantler
Scion Extremist
Scion Flesh Patcher
Scion Harlot
Scion Matron
Scion Repressor
Trueborn Advisor
Trueborn Bone Shaper
Trueborn Bonesplicer
Trueborn Conspirator
Trueborn Element Wielder
Trueborn Provoker
Trueborn Soul Render
Trueborn Tenet Enforcer
Trueborn Vitae Hoarder