Ataraxia

(You may cast a legendary instant only if you control
a legendary creature or planeswalker.)
Return any number of target spells to their
owner's hand.
If it's your turn, you may instead end the turn.
(Exile all spells and abilities from 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.)