I really loved Stone Wagon Druid before Uldum appears because of crazy tempo swings and a lot of surprise moments. With Untapped Potential we have another ultimate tempo swing card for druid (which probably will be nerved sometimes).

Untapped Potential provides the biggest advantages with Starfall (=board clear), Hidden Oasis (=heal and taunt)and Wisps of the Old Gods (=big tokens).

The idea was to combine those powerful cards with Stone Wagon Druid. Oaken Summons into Meat Wagon into Summoning Stone. Which is hard to kill all in one turn for the enemy. With Summoning Stone on your turn the action begins.

Oaken Summons into Archmage Vargoth (and another Oaken Summons from Vargoth) with a good chance and the stage is yours at turn 4 (or 3 with coin).

Another good combo is Twig of the World Tree any time before Medivh, the Guardian because his staff kills the twig refills your mana.

One Jade Idol will win any Mill/Fatigue match for you.

Poison Seeds is needed against Big Priest and also useful in other situations.