Equinox, Day Form

First strike, vigilance

At beginning of your upkeep and whenever a creature you control deals combat damage, put a maim counter on Equinox.

When Equinox leaves the battlefield, Equinox deals damage to each opponent and each creature they control equal to the number of maim counters on it.

{b}{b}, {t}: Exile Equinox, Day Form, then return it to the battlefield transformed under its owners control. Activate only as a sorcery.