The release of the new side-set, Conspiracy: Take the Crown, ushered a new mechanics that might appear in Commander, and possibly even other constructed games
It seems conceivable that he might have envisioned black having creatures that were hard to block in ways beyond swampwalk and fear
It has a fair body for its mana cost and Reach but its true power lies in flexibility as we may choose to pay the Plot cost to deal 2 damage to any target at instant speed and cast it on a later turn at sorcery speed for free
Consequently, currently at least, they all command pretty significant price tags, often in the triple digits
Once Evolution is cast, you find Trumpeting Carnosaur, keep the Discover train rolling until you have a big board, then finally grab Doomskar Titan with the last copy of Evolution and attack for the win