Commander is Magic: the Gatherings most popular format today, and with access to virtually all cards in the games 30+ year history, you can either make a deck really expensive (and uber powerful), or actually spend very little and still make a highly competent and synergized deck
One big advantage Nyxbloom Ancient has over similar effects like Zendikar Resurgent -- aside from making 100% more mana, that is -- is that it's a creature, which means it's much easier to cheat on its whopping 7cmc
Whenever its controller casts a spell of that type, they copy it, with copies of creature spells entering the battlefield as a token
I see this being pretty damn playable, especially in versions of those decks that make treasures, can ramp with green, or can do big mana stuff with devotion and cards like Cabal Coffers
To turn it into a win condition, just add Blood Artist or Vein Rippereach sacrifice drains your opponents, letting you control the board while chipping away at your opponents life totals
Shes definitely going to be a Red creature, though a Boros color identity would also suit her character
