I think it would be cool to add a new caste/new cards: Gods.

Each guild could have their own god...

Zil Warriors: Loki, the Trickster

Kotoba: Tengu, Harbinger of War

Desert Nomads: Ra, the Sun God

Pirates: Blackbeard, Lord of the Seven Seas

Noz: Arthur, God King

Runic Legion: Athena, Goddess of Warfare

Stone Linkers: Triglav,the Trinity (I'm not familiar with Slavic Mythology)

This of course would be after the Champion Cycle is complete

Part of me wants to say that Immortals are already related to the Gods, but at the same time they could just facilitate the Nomad God, there would be a few things I would change though about your suggestion:

1. Avalon: Arthur, God King, the Avalonian's are the ones that are based around the legend of King Arthur not Noz

2. Some of the guilds you have mentioned have Gods or Godlike figures already:

Noz: Dragon: The father of all Dragon Guemelites and Draconian magic.

Nomads: P'tola, Sol'ra, Naptys, or Kehper.

Runics: Nemaria or Thyrs. With there owns Gods already it is silly to use an Earth God for the Nomads and Runics.

3. Other then that I would put forth

Nehant: Dimizar, the New Nehant

Sap Hearts: Kei'zan, the World Tree

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Ty Boadicea for the awesome farewell gift. Now just to think up an avatar to go with it. Anyway, I'm still a Sap/Nomad/Pirates fan and user.

Not everything immortal is god. Gods have more properties, and in some religions are not immortals, actually. But my concern is this. A champion is a bit better and stands out among others in an army. A god would be much more powerful. How do you think they would balance this extra power among the 3 characters of the duel?
Unless they work on a scenario or concept of fallen gods, that they are actually stripped from their powers.

The God characters could be the type that takes the place of all 3 characters. In other words if you create a deck with a God, the God is the only character you can use.

I actually think that might be a good idea. Thy already have 'boss level' characters that are the only characters you can play. I don't think one for each guild would be a bad idea.

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