Commanders like Meren of Clan Nel Toth and Carmen, Cruel Skymarcher control the board with a critical mass of edict creatures
Specifically, Bant (White / Green / Blue), Esper (Blue / White / Black), Grixis ( Black / Blue / Red), Jund (Red / Black / Green), and Naya (Green / Red / White)
Having different options at your disposal makes you a nightmare
There are very few creatures in the whole of Magic which do so much for such little investment, and it is no wonder that Ragavan, Nimble Pilferer is being hailed as one of the best creatures ever printed
This is crucial because, as a general rule, a cards rarity directly impacts its market value
Two, art is very subjective, and the Eternal Magic rules don't like ambiguity