Definetly once per turn....as it is right now it's one of the most ridiculos card i'ven seen in a long while...2 mana to cycle through 18 cards or so.
I'm pretty sure the effect is blue/black though.
Maybe do a U/G version which returns lands, like this:

Creature - Human shaman (?)
Return a land you control to it's owners hand: look at the top 2 cards of your library. Put one of them in your hand and the other on the bottom of your library, then discard a card.
2/1
This card is atleast limited by the amount of lands you have in play, and the limit of 1 land per turn.