A good question for deck building is: Would rather have this or Heroic Intervention
Theyll struggle to remove a 9 Willpower character with a hefty Strength unless they have good removal and hes out of Medusas range
Cosmogrand Zenith is, by all means, a good card, and it will inevitably see a lot of play
Since you will likely have a large battlefield of Rats and Rat tokens, Coat of Arms makes them both amazing attackers and defenders
This means a Shifted card is more economical to place on the field, and a Shifted character can also challenge on the same turn it is played provided the Ink is dry on the bottom card
It needed to be affordable, allow for play outside of our trusted playgroup, and the decks needed to be constructed in a manner that was basically correct for Commander