Daru, the Hack

{t}: Each player exiles the top card of their library with X time counters where X is the mana value of the nonland card exiled
this way with the highest mana value. If the highest mana value is 0, untap Daru.
Remove two time counters from a card in exile you don't own: Untap Daru. Activate
only as a sorcery.