Hive Mind

The whole point of a symmetrical effect is that it looks fair until someone breaks the symmetry, and this is the cleanest break in the game. Force everyone to copy your spell and you have built a Pact problem nobody else asked for: the Pact cycle of spells (Pact of Negation, Slaughter Pact, and the rest) cost nothing to cast and demand a tax on your next upkeep. Hand every opponent a forced copy of one, and they all owe that upkeep tax with no warning and no way to decline; whoever cannot pay loses. The enchantment turns a "free" spell into a kill condition aimed at the table while you, the original caster, paid the cost knowingly and simply pay your own tribute. That is the combo it is famous for, but the design idea underneath is broader and stranger: it converts every instant and sorcery into a group ritual, which means it punishes opponents for casting spells too. Every counterspell they fire copies onto your stack, every burn spell hands an extra target's worth of value back at them. It does nothing on its own and demands you weaponize the copying rather than merely enjoy it, leaving a card that plays like a puzzle box instead of a payoff. The symmetry is the bait; the asymmetry you smuggle in is the whole game.