Strixhaven Stadium

An alternate win condition wearing a mana rock's clothes, and the mana ability is not the afterthought it looks like. Tapping for one colorless also advances the meter by a point counter, so even a passive board is inching toward ten without swinging. The combat clause is where the machine really lives: every creature you control that connects with an opponent adds a counter, and the tenth ends that player outside the life total entirely. Note the arithmetic that governs the race: a counter goes on per attacker that gets through, not per point of damage, so a lone 5/5 advances the meter exactly as much as a lone 1/1. Going wide and connecting with many bodies is the fast lane; a single fat threat is slow. The interactivity lives in the two-way meter, because this is not a counter that only climbs. When a creature deals combat damage to you, a counter comes off, so an opponent who can push through blockers is defusing your clock rather than building their own. That downside never threatens you directly (it only sets back your own kill), but it means you cannot sit at eight forever while the board stalls: you have to keep attacking profitably faster than they can attack back. It sits in a small family of combat-damage-as-resource payoffs, but this one folds the state of your own defense into the win condition's math, turning an incidental trigger into a genuine race.