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Frostwalk Bastion
Snow Land
: Add . : Until end of turn, this land becomes a 2/3 Construct artifact creature. It's still a land. ( can be paid with one mana from a snow source.) Whenever this land deals combat damage to a creature, tap that creature and it doesn't untap during its controller's next untap step.
uncommon · #240 · mh1
Previewed: May 22 · Spoiled by JiRock