The first question we need to answer to figure out how many decks to have in your roster is what makes Commander such an attractive format to keep brewing in?
Its obviously a much less powerful card overall, and you cant just throw it into a deck with no concern for what else is in there, but its possible there is a deck built with The Cauldron of Eternity in mind and then this deck could want Gray Merchant, but it really has to be a dedicated self-mill deck for it to work, because if you cast Gray Merchant and it dies naturally (which is the most common play pattern), it doesnt work with the Cauldron unless the Cauldron isnt on the battlefield yet
Together with Kyler, a kind of backup for boardwipes
Damage, a card from your opponent, and a treasure for you is an amazing trifecta
Edge of Eternities Review Showcase Art As with every set nowadays, youll be able to find a plethora of special showcase art cards in both the play and collector boosters