Wolf of Devil's Breach

The attack trigger is a conversion engine: it turns a card in hand into damage scaled to that card's mana value, aimed at a creature or planeswalker. The design lives on three restrictions. The ability only fires on attack, so the Wolf has to commit to combat against the same board it wants to clear, which makes its 5/5 body a worse defensive piece than the toughness suggests. The damage can only point at creatures or planeswalkers, never at players, so this is removal and never reach. And you pay both mana and a card every time, with nothing replacing what you pitch: this is one-way conversion, not filtering. That last point sets its real ceiling. The trigger rewards a hand stocked with expensive spells you would rather not draw twice, because a discarded five-drop throws five damage and a discarded bomb clears a blocker before damage. But the floor is thin: pitch a land or a cheap spell and you get a rounding error, since mana value is the whole scaling formula. So the Wolf is not a fix for flooding (extra lands convert to nothing) but a payoff for a top-heavy build that treats its clunkiest cards as ammunition. It asks you to keep swinging, keep feeding it, and accept that the bigger the card you throw away, the bigger the bolt.