Permafrost Trap - Worldwake (WWK)

Permafrost Trap - 2, Blue, Blue

Instant - Trap

Uncommon - Worldwake (WWK)

If an opponent had a green creature enter the battlefield under his or her control this turn, you may pay Blue rather than pay Permafrost Trap's mana cost.

Tap up to two target creatures. Those creatures don't untap during their controller's next untap step.