Scour from Existence

The price is the whole proposition: seven generic mana buys the right to exile anything on the battlefield, no questions asked, at instant speed. That answer-everything clause is what justifies a number that would otherwise be laughable for a single removal spell. Most colorless removal in this vein carries a hedge: it hits artifacts only, or noncreature permanents, or asks you to pay life or sacrifice something. Scour from Existence drops the hedge entirely. Land, creature, planeswalker, enchantment, the opponent's whole engine in one card: the target line reads "permanent" and means it, and the exile clause means indestructible and regeneration and graveyard recursion are all irrelevant. The colorless cost is the point too, since a deck running no colors at all (or every color) can still reach for it without bending its mana. What you are paying for, then, is universality at the expense of tempo. Seven mana for one removal is a rate that only makes sense in a deck that has already stabilized and can afford to trade a full turn's worth of mana for the cleanest possible answer to a problem nothing else in its colors can touch. It is insurance, sold at insurance prices: the spell you run not because it is efficient but because it never whiffs.