Grenzo, Dungeon Warden

The repeatable activation reads from the wrong end of the deck, and that inversion is the whole engine. Most library-as-resource cards work off the top, where you can fix what you draw; this one mills from the bottom, a zone you cannot scry or sculpt by ordinary means. That apparent downside is the point: it turns bottom-of-library placement into deliberate setup, letting scry effects that leave a card on the bottom and outright tuck effects load the floor of your deck with creatures you intend to reanimate for two mana a pop. The power clause is the governor. He only cheats in creatures with power less than or equal to his own, so the X in his casting cost is not just a body, it is a ceiling on the toolbox: pay more, reach further. That coupling of one number to two jobs (his size and his reach) is the tidiest part of the design, and it rewards building a curve of creatures rather than a single fatty. His deckbuilding question is unusual: not "what's my best creature" but "how do I get my best creatures to the bottom, in the right order, before I start grinding." The activation still feeds a graveyard when it misses, so the engine produces something on both outcomes. A self-mill reanimator built around a zone most games treat as inert dead space.