The Time Stone

{t}: Add one mana of any color to your mana
pool.
{1}, {t}: End the turn. Activate this ability only on
your turn. (Exile all spells and abilities on the stack,
including this card. Discard down to your maximum
hand size. Damage wears off, and "this turn" and
"until end of turn" effects end.)
"You're full of tricks, wizard. Yet you never once used
your greatest weapon."