Mindwrack Demon

Four life a turn is the tax, and the enters-the-battlefield mill of four is the down payment on avoiding it. Delirium was built as a threshold mechanic that asks a deck to diversify its graveyard rather than simply fill it, and this creature is where that tension lives in a single card: a 4/5 flier with trample that costs you nothing extra to cast but demands you assemble four card types in the yard before your next upkeep or start bleeding. Milling yourself four cards helps, but a graveyard of four sorceries counts as one type; the mill here is not about volume but variety. That inverts the usual black self-mill drawback, where dumping cards is pure upside for reanimation and dredge shells. This body punishes you for a monotonous graveyard, so the deck around it has to run instants, artifacts, enchantments, lands to the bin, whatever it takes to trip the count. Get there and the demon is a genuine overperformer for its cost, a hard-to-block clock that closes games. Miss and it is a self-inflicted burn spell attached to your best threat. The design pins the reward and the risk to the same axis: the mill that threatens your library is also the fastest way to satisfy the condition it created, and a delirium-minded builder has to decide whether four cards toward the count is worth four cards off the top.