"Saw Sam Black play something like this at the NRG (he went 0-3 in the Pioneer section, which just means there is room to improve!). Basically Courser/Excavator + Swordtooth/Ghirapur lets us play a ton of lands from our GY or the top of our deck, which empties our hand to trigger Orrery or to make a bunch of clues with Tracker. Sylvan Advocate is like a vigilant Tarmogoyf in this deck and they pump up our Mutavaults and Nissa Lands. Borrower is our sole piece of interaction, and it serves double duty as it ensures they won't trigger Ghirapur."