Sarkhan, Fireblood is that turn 2-3 ramp card you want to be casting in Dragon Tribal, basically a superior Urza's Incubator since for most turns you'll only be casting one Dragon per turn and Sarkhan also mana-fixes and also can rummage for you if you don't have a Dragon spell to cast
ACR also gave us Brotherhood Headquarters as a color fixer for assassin decks
It is important to remember that these numbers are estimates only, and each person's experience will always vary with what cards they can find for themselves
Once youve built up a powerful board, its almost always keeping a little mana in reserve for Heroic Interventions excellent insurance, and when playing green youll frequently have the mana to spare without tipping other players off
So yeah, Volrath, the Shapestealer has a TON of cool tricks up his sleeves
You may wind up wanting to make some quick upgrades to this deck after you play it out of the box