Red Elemental Blast, Pyroblast, Dispel, Swan Song & An Offer You Can't Refuse provide a crazy ceiling of value for a single Mana
Birth of the Imperium works best in token decks, but it creates relevant bodies, forces some removal, and draws you cards - three pieces of value that will never be unwelcome
You can also pay three mana and tap it to make a 2/2 with every creature type - we dont expect that to be the most important part, though
So which one do you choose all 3 because you are definitely going to run 3 of these in any angelic white deck
Lets do some comparing: I dont want to compare TSR here (no Collector Boosters) or Commander Legends (see gimmick below) but you can see that Forgotten Realms is going to play out a lot like Kaldheim did, only without the Vorinclex to be the chase card
Fetches give meaningful mana flexibility to all Magic formats theyre legal in and competitive Commander is no exception