Stun the cursed unit (for as long as it is cursed).
Permafrost is a Curse.
How to Get
This card can also be obtained from Card Packs. Diamond Chests and Card Packs can give Premium versions of this card.
Permafrost should be used as a form of cheap removal. While it doesn't remove the unit entirely it will make it so a creature can't attack or block, and it can be used to deal with annoying creatures like Dawnwalker .
When Permafrost is removed, the unit can attack and block immediately.