Legendary Artifact

At the beginning of your upkeep, put a time counter on The Moment.
{2}, {T}: Untap target creature you control. It phases out until The Moment leaves the battlefield.
{3}, {T}: Destroy each nonland permanent with mana value less than or equal to the number of time counters on The Moment. Then sacrifice The Moment. Activate only as a sorcery.

Artist(s): Patrik Hell