Creature - Human Wizard 1/1, 2U (3) {U}, {T}: Target snow land becomes a 2/2 blue Elemental creature with flying. It's still a land.
Illus. Stephen Tappin
7/15/2006: Balduvian Frostwaker's effect has no duration. The snow land is a creature as long as it's on the battlefield.
7/15/2006: If an affected land later loses the supertype snow, Balduvian Frostwaker's effect doesn't end. The land will remain a creature.
8/1/2008: A noncreature permanent that turns into a creature is subject to the "summoning sickness" rule: It can only attack, and its {T} abilities can only be activated, if its controller has continuously controlled that permanent since the beginning of his or her most recent turn.