unless there are only 10 people in the entire clan, you should probably aim for
annihilation instead lol
decimate = reduce to a tenth (1000 soldiers becomes 100 soldiers, etc)
annihilate = reduce to
nothing
not saying he should wipe himself out ofc, but once everyone else is dead all he has to do is say "poison clan's disbanded"/"i'm no longer part of the poison clan" & poof, it's gone
also he should do it regardless of the outcome, fuck these people