Suffocating Wave

Play only if Pacifica, Wave Transformer is on
the battlefield under your control
Choose X creatures controlled by the same opponent. At the start of your next X turns,
put a -1/-1 counter on each of them.
{x}{u}Shuffle this card back in your library
"When I dislike my someone, my powers give
them a hug. It's not my fault if that kills them." —Pacifica, Wave Transformer