Master Mutator
From Warhammer - The Old World - Lexicanum
Commanding the Skaven’s hellish legions of twisted flesh are the Master Mutators. These mad Skaven hold the foulest secrets of their craft, trickling the information to the Master Moulders, empowering them with just enough knowledge to protect their Clan while keeping the rest secret to prevent being overthrown. It’s not known what abominations can be attributed to the Master Mutators, but some believe that not all of the terrors found in the Old World are by the will of the Changer of Ways. The Packmasters claim in hushed tones and with shudders that the Master Mutators’ best subjects are themselves
