Myojin of Infinite Rage
Every Myojin in the cycle bought its splashy effect with a single-use clause: cast it from hand, earn one divinity counter, and that counter pulls double duty as both indestructibility insurance and the ammunition for the activated ability. Spend it and you fire off a destroy-all-lands effect bolted to a 7/4 body; the instant it leaves, so does the protection. You cannot have both twice, and that constraint is the entire engine. The land destruction reads as devastating in the abstract, but it forces a brutal accounting between the only thing keeping the creature alive and the resource it exists to expend. The body is the deeper liability: four toughness on a ten-mana spirit means that once the counter is gone, nearly any removal or a single profitable block finishes it, and you have just stranded yourself on an empty board with no lands to rebuild from. Because the destruction is symmetrical, the play pattern is to land it, wreck everyone's mana, and ride a fat (and now mortal) threat through the rubble before opponents recover. It is the most all-or-nothing member of a cycle already built on all-or-nothing math, and the distance between its printed power and its practical reliability runs wider than any of its siblings'. One meter, one detonation, no second pull.
