Omniscience

Ten mana for the right to stop paying for anything is the worst joke in Magic and also the entire point. The cost is not really three blue and seven generic; the cost is that you have to find a way to cheat it onto the battlefield, because casting it honestly means you have already won or already lost by the time it resolves. That tension is the whole reason it exists: the card promises a turn where every spell in your hand is free, and dares you to assemble the engine that gets there before turn ten. The classic line pairs it with a sufficiently large mana ritual or a way to put it directly onto the battlefield, then dumps a hand that ends the game in a single wave. What separates it from a normal payoff is that it imposes no restriction on what you cast: not just instants, not just one spell, not your commander only. Everything in hand, all at once, for nothing. The honest static abilities that read "you don't pay costs" are usually fenced in by a card type or a single use; this one removes the fence entirely and trusts the board state to be the only limiter. It is less a finisher than a permission slip, and the games it produces tend to be over before an opponent can meaningfully change the outcome of whatever the free spells were.