Blazing Hope

The condition is the whole machine here, and it runs backwards from how white removal usually prices itself. Most one-mana white answers buy their cheapness with a ceiling on what they can hit: a toughness cap, a converted-mana cap, a tapped-only clause. This one inverts that. It can exile anything with enough power, no destructibility or size exceptions, including the indestructible threats and giant fatties that white otherwise has no clean way to remove for a single pip. The catch is that the threat has to be big enough relative to how low you've been pushed: at a full twenty life you need a power-twenty creature, which is a rare enough sight that the card mostly sits dead in your hand until you're under pressure. It scales with your own desperation. The lower your life, the wider the net, and the cards that put you low (an aggressive opponent, your own life-payment effects, a damage race gone sideways) are exactly the cards that make a power-four or power-five threat suddenly legal to exile. That makes it a removal spell that gets better precisely when you're losing, which is a rare and slightly perverse design axis: the price of the exile is your own danger, paid in advance by the game state rather than by mana. As a one-mana instant it lives in the window where you can answer a haymaker the turn it lands, but only once you've already bled enough to deserve the answer.