Marrow-Gnawer

Target creature gets -2/-2 until end of turn. Flashback—1B, Pay 3 life. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.) This creature can't block.

Search your library for a card, put that card into your hand, then shuffle.

(T: Add B.)

All creatures gain fear until end of turn. (They can't be blocked except by artifact creatures and/or black creatures.) Cycling 1B (1B, Discard this card: Draw a card.) When you cycle this card, you may have target creature gain fear until end of turn.

(T: Add B.)

Whenever a creature you control deals combat damage to a player, that player discards a card.

B, Discard a card: Regenerate this creature. Threshold — As long as there are seven or more cards in your graveyard, this creature gets +2/+2 and can't block.