Ultimate Big Chill

Flying, Hexproof
Absolute Zero- When Ultimate Big Chill
transforms, tap all creatures target player
controls. Those creatures don't untap during
their next untap step.
Cumulative Upkeep {1} Transform to Big Chill,
Cryo Specter
"An ascendant force of frost and wings, Ultimate Big
Chill commands the cold with unrivaled mastery."