Pretty simple theme. Play like a control deck, ramp up, and then drop Planeswalkers and Doubling Season while protecting with boardwipes and countermagic. Most PW's can fire devastating ultimates immediately if Doubling Season is out.
Obviously the manabase could be stronger with dual-lands/old fetches but I don't own any, nor some of the pricier cards (aka the maybeboard).
Garruk, Primal or Sarkhan Vol + Doubling Season is broken.
Tamiyo can emblem immediately with DS out.
Nicol Bolas can also ult immediately and seal the game.
Generally win with incremental advantage gained by PW's and boardwipes. Keeping PW's alive is key.