Golden Demise
The trick with a symmetrical sweeper is convincing your own board to survive it, and ascend solves the problem by rewriting the spell's text rather than your sequencing. Cast early, it plays as pure attrition, a minus-two-two that costs three mana and clips your creatures alongside theirs. Reach ten permanents, though, and the city's blessing flips the second clause on: the same card now shrinks only your opponents' board and leaves yours untouched. That conditional rewrite is the whole design, and it distinguishes the card from wraths that ask you to commit nothing beforehand or recover afterward. Here the asymmetry is paid for by the board development an aggressive or go-wide deck is already generating, so the threshold tends to tip right around the turn you want to clear a clogged ground while keeping your own attackers intact. The size band does the rest of the work: minus-two-two is small enough to spare real threats and give a swarm deck room to overload it, but large enough to sweep the small creatures it was built to punish. It never pretends to be a catch-all answer. It is a tempo-priced tool for crowded boards that asks you to have built the crowded board in the first place.
