First and foremost, this deck wins games by generating COLOSSAL boards with Primordial Protector, N'Zoth, God of the Deep, and Y'Shaarj, the Defiler, before reinforcing them with the sleeper OP Vivid Spores.
The three main reasons to play this deck:
1) Win condition is extremely satisfying and quite unique in this meta. They NEVER expect Vivid Spores, and even on relatively small boards it can just totally devastate their game plan. Additionally, N'Zoth, God of the Deep and Y'Shaarj, the Defiler work incredibly well together in this deck - they both summon big taunt and rush minions (see list below).
2) Survivability. This deck has a very efficient early game and will almost always survive aggressive decks until you can Tidal Wave - a card that you will frequently find in hand due to Primal Dungeoneer and Primordial Protector. Tidal Surge and Chain Lightning (Rank 1) are your early removal until then.
3) Synergy. Using only Nature Spells makes Primal Dungeoneer an incredible card draw tool - it will always draw either Circus Amalgam or Primordial Protector, as well as a removal spell or Vivid Spores. Every Corruptable card in this deck is reliably Corrupted by virtue of the deck's curve, and the 0-cost minions from Y'Shaarj, the Defiler (see list below) are excellent targets for Vivid Spores.
HOW TO PLAY: This deck wins by making big boards and killing the opponent with them. Do NOT play a control style game with this deck, you will lose. You have insane tempo so use it before it runs out. Don't worry about saving Corruptable cards until they are Corrupted; if you need to play them then throw them out there.
I've had huge success and fun with this deck. However, it struggles against Control Priest, Celestial Druid, and Burn Mage. Any feedback is appreciated. GLHF