I am pretty hard core into tabletop gaming, and I thought it would be pretty fun to create an actual playable analogue to Dragon and Pete's game. From what I can recall/find in the archives, the game works basically as follows:

• You need at least 3 players: two warring gods and a mediator (I.E. Dragon, Pete, and the kitsune, respectively)
• Each god has a temple, which serves as the base of their power
• Each god has a number of followers who can further their goals on the moral plane, and one Avatar who they control directly
• The gods' avatars will eventually face off and one will kill the other
• The bulk of the gods' machinations are to ensure that their respective avatars will be victorious

Some things that would have to change for a real version would be:

• The mediator would have to control each player's followers and interpret the ramifications of the players' actions
• There would have to be some limitations on what players could do and when
• There would have to be some organized mechanics for how avatars and followers function in the game

I am thinking that the d20 system core rules would be a good starting point for the crunchy parts of the rules.
Does anyone else have any thoughts or ideas on how I could make this work as an actual game?

Well, it just said the avatars face off in a duel, not that it is a duel to the death...

Right, got that slightly wrong.
And this is why I am trying to make sure I know what the goals are before working on the system.

This is a fun idea! I'd worry that the core concept is so broad in scope that it'd be difficult to keep mechanics and game progression even remotely comprehendable, but definitely cheering on your efforts!

Depending how you wanted it to play out, it might be fun to incorporate a deck of action cards to introduce random events, like the chance cards in monopoly.

Hm... A deck of random events might make the mediator's job easier. That way the mediator wouldn't necessarily have to decide when something important is happening on the moral world.