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

Despairing Trueborn Soul
Dishonored Trueborn Spirit
Enraged Trueborn Lightstealer
Malicious Scion Shadow
Malicious Trueborn Essence
Scion Assassin
Scion Brutish Converter
Scion Captain
Scion Chaotic Swarm
Scion Deathmender
Scion Dismantler
Scion Extremist
Scion Flesh Patcher
Scion Harlot
Scion Repressor
Trueborn Advisor
Trueborn Bloodgiver
Trueborn Bone Shaper
Trueborn Bonesplicer
Trueborn Conspirator
Trueborn Death Synergist
Trueborn Hopedasher
Trueborn Provoker
Trueborn Shadowmaster
Trueborn Soul Render
Trueborn Tenet Enforcer
Trueborn Vitae Hoarder