This combo does work.

Earthcraft reads: Tap and untapped creature you control: Untap target basic

land.

Relevant rulings from Crystal Keep:

     Since it taps a creature as a cost, it must be used on an untapped

     creature. [D'Angelo 1997/11/11]

     It can tap a creature with summoning sickness. [bethmo 1997/11/11]

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Olwen Wee

owee@checkfree.com