Mimic's text:
Ongoing: This minion's power is equal to the highest power printed on a minion card in play.
What is the power of 'Mimic' while it is in the deck?
I.E. can a G.E.L.F. or Sprout pull it from the deck if Zombie Lord is in play??
Ongoing abilities are active only when the minion is in play.
When it is in the deck, the Mimic uses it's listed power of 0. Any ability that can affect a minion of power 0 in the deck can affect the Mimic