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Just a quick question - if Kheradruakh The Decapitator has a retinue of mandrakes then when Kheradruakh uses the rule Shade Stalker, do the mandrakes also follow Kheradruakh onto the battlefield?
I don't think Kheradruakh has any option to take any kind of retinue. He is not an Independant Character, he's just a 1 model unit.
The meat things seek to destroy ourselves. They hunt us as we hunt them but they are weak and uncertain. Bring them understanding of the power of ourselves through our strength and their fear. The inferior flesh will be entirely destroyed, all fragments will be smashed. Ourselves will fight to the last, all weak flesh must be consumed
As stated the Decapitator isn't an independant character, thus he is unable to join a unit of anything. This does naturally mean shade stalker has no interaction with anything other than himself.