This genius stroke of villainy was born as I looked at all the creature types of Burning-Tree Emissary and saw that I could get a "free copy" of Ashling's Prerogative out through the BTE's ETB.

Well, I had to abuse that interaction along with Bosk Banneret and Centaur Omenreader to get all my even-costed shamans out with haste and for zero colorless mana. From there it spiraled out of control to what you see here: free shamans and burn.