Marang River Regent // Coil and Catch

Commander is the natural home for Marang River Regent // Coil and Catch — seven mana is a reasonable top-end in a 40-life format, Dragon tribal support is deep, and the steal effect on Coil and Catch scales up against the expensive threats opponents play in long games. In Standard and Pioneer, it's legal but competing against a faster clock where a seven-mana do-nothing-until-it-resolves creature is hard to justify outside dedicated Dragon shells. Modern has enough efficient interaction to make this a risky investment at that cost, though reanimate strategies could find a use for it. Legacy and Vintage have far more broken things to do with seven mana, so it won't see play there outside of pure fun. Oathbreaker, like Commander, gives it room to breathe — if your signature spell accelerates mana or reanimates, Marang River Regent // Coil and Catch is a legitimate payoff.