Permafrost Trap - Worldwake - 34

Instant — Trap

Mana Cost: {2}{U}{U}

If an opponent had a green creature enter the battlefield under their control this turn, you may pay {U} rather than pay this spell's mana cost.
Tap up to two target creatures. Those creatures don't untap during their controller's next untap step.

Uncommon · Worldwake · #34 (WWK)

Illustrated by Howard Lyon