That's a game-ender waiting to happen, especially in decks like G'raha Tia, Scion Reborn, Isshin, Two Heavens As One, Baylen, the Haymaker, or any go-wide Commander shell looking for a top-end swing spell in disguise
While Rhys is vulnerable at 1/1, and his ability is quite expensive, his low mana cost makes him easy to weave into a turn, forcing your opponents to answer him immediately or else
The check land cycle is fine, but only really good in budget decks with extra Basics to ensure they enter untapped
With one or two in the deck, we can see this getting play
Brawl Legal Vintage Legal Timeless Legal Commander Legal/GC Pauper Not Legal Oathbreaker Legal Penny Not Legal On the Commander Game Changer list (view all) Toolbox Buy This Card Notes and Rules Information for Opposition Agent: While controlling an opponent, you make all choices and decisions for that player