Theorycraft for AoO Highlander Druid, based upon my current Highlander Druid deck that I've piloted to rank 5 this season. Designed to be played in Standard, once the Year of the Phoenix rotation hits.

A combination of treant druid and embiggen/dragon druid, with a highlander twist. It works by applying the best of both strategies side-by-side to build a tall and wide board.

The general game plan is to apply pressure early on with the treant package to maintain board control and while you build up buffed dragons. There are many great combos in this deck. There is a lot of value generation (maybe too much?) which adds a lot of versatility. Cards such as Worthy Expedition, Vulpera Scoundrel to pull Blessing of the Ancients or Power of the Wild when you have a wide board, or adding more treants via Force of Nature, or helping trigger Garden Gnome and Anubisath Defender by selecting 5+ cost spells from discover.

More combos:

Turn 1 Treenforcements (Summon treant), turn 2 Shrubadier, + Coin + Aeroponics
Turn 3 Imprisoned Satyr, turn 4 Garden Gnome, turn 5 Cenarius (If reduced by Satyr)

Turn 4 Garden Gnome, turn 5 Force of Nature + Aeroponics + Anubisath Defender

The classic Embiggen + Frizz Kindleroost. Some great minions to have buffed include Anubisath Defender, ANY dragon, Oasis Surger, and extra sticky Crystal Merchant or Faerie Dragon and giving minions like Garden Gnome or Shrubadier more stats in the late game.

Zephrys the Great (Brawl or other 5+ cost card) + Anubisath Defender

Elise the Enlightened is great with Anubisath Defender, a second Frizz Kindleroost, any dragon reduced to lower cost by Frizz, getting great value from double [Hearthstone Card (Worthy Expeditions) Not Found], lots of draw from Aeroponics (if you have treants on board), 0 cost dragons added to hand by Dragonqueen Alexstrasza and other cards in hand reduced by Imprisoned Satyr.

The newly revealed AoO cards look like a great combination to help bridge out some of the big dragons and fill a gap from the loss of cards that I currently use such as Floop, Zilliax, SN1P, Mulchmuncher and Nightmare Amalgam. They look good to control tempo as well as setting loose a turn 5 Dragonqueen Alexstrasza, Cenarius, Goru the Mightree or any of the other dragons.

Possible additions or removals:

- Cobalt Spellkin - Might sometimes add too much clunk to the hand

+ Frenzied Felwing - Good with Embiggen buff

+ Any Lifesteal minion -  good to be buffed by Embiggen also, if healing is a problem.

+ Any crazy/OP cards yet to be released from AoO!!