The Persona series as a whole, including the other Shin Megami games... If we count summoning them as playing them, but it's basically pokémon isn't it.
Fate/Grand Order also features a huge roster of mythical figures, but actual gods make a far smaller portion of them. Very few games get to feature, Ishtar, and, Quetzalcoatl, together with Shakespeare and Merlin.
For me, trying to read the actual protocol or even tutorials that try to explain the protocol in a more approachable manner, didn't help at all. It's no understatement that ActivityPub itself is a mess.
But reading the Fedify documentation and describing "activities" with the library helped a lot more!
Even if you don't plan on writing Js/Ts, I recommend the Fedify tutorial.