There must be a unit of Black Orcs in Grimgor's army. This unit of Black Orcs are as scarred and grizzled as Grimgor, veterans of his days in the wastes. The bodyguard is infamous for its standard bearer, Taugrek the Throttler, who recaptured Grimgor's personal banner when it fell in battle against the hordes of Vardek Crom.
Grimgor may only join this unit, and no other character may do so. If he does so, the bodyguard will be Immune to Psychology and will Hate everyone.