human frailty is good for snapcaster and zealous conscripts but unfortunately killing them doesn't really do much of anything. also i'm not sure if 4x slip 4x victim is that good a sideboard; i can't think of a matchup where you'd want that much spot removal over, say, mutilate (assuming you're running a decent number of swamps). i'd definitely keep a couple of slips, as that card is fantastic, and maybe 1-2 victims i dunno. but if you can support victim easily i'd say just keep a couple of mutilates sideboarded instead. did you post a decklist anywhere?