Darksteel Mutation This is a top-tier answer for cards from the best commander decks
Faerie Formation You can widen your board presence and develop card advantage in one fell swoop with Faerie Formation
Triumphant Adventurer The simplest version of fantasy games often boils down to similar experiences in both Magic and D&D: take a risk going into the dungeon (or gaming store), pay the price in hit points (or from your wallet), and come out with the unknown treasures within (booster packs)
They can choose to put two +1/+1 counters on a creature they control at the beginning of your turn to make it larger, but if they do, they wont be able to attack you until your next turn
In the demo deck, Ari suggested we just make a mana stone and name it generically as a powerstone
An energy deck is completely novel territory for a Commander precon (at least until we see it again in Modern Horizons 3 ), which makes Science