Equipoise
A symmetry-breaker disguised as a fairness engine. The phasing here is the clever part: rather than destroying the opponent's excess permanents, it phases them out, which means they return at the player's next untap step exactly as they left, with every counter, aura, and equipment intact. The trick is that the imbalance persists, so the excess phases right back out on your following upkeep, an indefinite tax that never resolves. The "in excess of the number you control" clause is what keeps this from being a Wrath: you never gain ground in raw count; you simply guarantee the opponent can never field more lands, artifacts, or creatures than you do without the surplus going dormant turn after turn. That recurring leash rewards the player who keeps a deliberately small, controlled board and punishes the ramp-and-flood plan most decks are built around. The targeting structure is the subtler weapon: the spell targets only the player, while you merely choose which of their permanents phases out, so hexproof and shroud on individual lands, artifacts, or creatures offer no protection. You decide which piece sits out the turn, stranding the opponent's most important permanent while leaving their dead weight on the table. It is a soft lock that never quite locks, the kind of design Wizards rarely revisits because phasing as a recurring control tool reads as obscure even when the strategic effect is brutal.
