Avatar Aang, for instance, knocks it out of the park with fantastic art, flavor, and abilities
Paying one mana to reorder the top three cards of your library, and then tapping it to draw a card is amazing with a Commander that cares about what the top card of your library is
Nihiloor Nihiloor wants to be the top-end of a theft deck
You don't have to grind for months to build a single deck and then for months more if you want to switch
I mean, sure, its only five mana more and returns to your hand when it blocks, but at least Zephyr Spirit gets one more point of toughness
7 Survey The Battlefield Building a deck and studying the intricacies of the available cards is crucial, however, if one does not understand how the battlefield works, all this background information will be for naught