Icy Blast 
Instant
Tap X target creatures. Ferocious — If you control a creature with power 4 or greater, those creatures don't untap during their controllers' next untap steps.
Legality
standardNOT LEGALpioneerLEGALmodernLEGALlegacyLEGALvintageLEGALcommanderLEGAL