Z-Wave

Destroy all creatures with power {x} or
greater. For each creature destroyed this way, return
a creature card with lesser power from your
graveyard to your hand.

"You were looking for your precious Zordon, but
when he sacrificed him with the Z-Wave, it wasn't
just his particles that spread across the universe.
Get it? The evil was purged from my being, and the
waves scattered it across space." -Rita Repulsa