Alter, Void Breacher

Vigilance, Reach

As you cast Alter for the first time each turn, if an opponent has a card in exile, draw a card.

{x}{c}{t}: Return Alter and target nonland permanent
with mana value X to their owners' hands.

Discard a card: Target opponent exiles a card in their
hand. Activate this ability as a sorcery and only once
each turn.