A slight improvement to Phyrexian Denouncer in that this can flying and kills larger things. Still, not really a great cost for such a marginal effect. But, to its credit, it only has one card that it can be called inferior to in the same "costs exactly the same, isn't a permanent, and has a similar (or better) effect" category that I judged the Denouncer on: Gild. I guess it's good for 4-drop black removal then? Eh... No. It's still bad. Better than Denouncer, but still bad.
Pros: Flies, Crippling Fatigue on a stick, not Phyrexian Denouncer
Cons: Requires tap, requires sack, 2/2 for 4