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Does a unit lose Feel No Pain if the attached Painboy leaves the squad, or is killed?
I.E. can Mad Doc Grotsnik be attached to one mob of 30 orks (hence giving them FNP) and then second turn leave and attach himself to another (different) mob of 30 orks giving them FNP as well?
In the Case of Mad Doc Grotsnik, the FNP follows him. So leaving one squad to another would indeed give the other squad FNP but the first squad now Grotsnik-less would lose it.
So short answer yes, if Grotsnik (or a dok in a nob/flash git mob) dies or leaves a mob, that mob loses Feel No pain.
Gargrimz Green Deff
W:10 D:4 L:5