User blog comment:Kygehn/Spirit Visage's Forgotten Sister/@comment-6301771-20140101072303/@comment-4952847-20140101102652

Pretty much nailed it.

Executioner's Calling is an AD parallel to Morellonomicon, and the real reason it is unused is because it is simply not gold efficient.

Morellonomicon gives stats worth 2995+ gold for 2200 cost, not including the Grievous Wounds. Executioner's Calling gives 1900 gold for 1900 cost, not including the Grievous Wounds.

The only things that it needs to become more useful are more of the same stats.