Regarding the legality of the cards: Magic: The GatheringFINAL FANTASY (FIN) is a Standard-legal set Magic: The GatheringFINAL FANTASY Commander (FIC) and FINAL FANTASY Through the Ages (FCA) are Commander-, Legacy-, and Vintage-legal sets, and individual cards are also legal where already available in other formats Magic: The Gathering FINAL FANTASY Play Boosters contain cards from FIN and FCA
Granted, you have to fill your graveyard with different permanents first before you can summon the Spirit God The Ancient One, but that's very easy to achieve if you're playing Dimir colors, anyway
The ATLA Magic The Gathering set has introduced a collaboration that fits entirely within the existing Magic color pie
As a brief mathematical aside (feel free to check my work, Quandrix nerds), here is a short comparison of non-generic/staple overlaps with the appropriate predecessor across each Secrets of Strixhaven Commander deck, not counting Sol Ring or Arcane Signet nor generic/staple lands: 7 cards from Silverquill Influence overlap with Silverquill Statement 10 cards in Witherbloom Pestilence to Witherbloom Witchcraft 10 cards in Prismari Artistry to Prismari Performance 5 cards in Lorehold Spirit to Lorehold Legacies 9 cards in Quandrix Unlimited to Quantum Quandrix Seeing the data laid out as such, it's hard to justify my vibes-based analysis as anything more than a poorly calibrated vibes antenna
to 10:30 a.m
This is another way to know youll have a spell to cast to trigger off Codies ability even if you dont have one in your hand: when the upkeep trigger to take the last time counter off this spell in exile goes on the stack, go ahead and activate Codie, and then cast Inspiring Refrain