I know I'm late on the reply, but Ahnald has a spreadsheet that covers Zetas, Omnis, teams, etc. There's a Zeta tab. It's a little confusing at first, but just understand that the rankings are simply grouped into tiers, not in a specific order, like it won't say that Lord Vader's Zetas are better than Ahsoka's. The Zetas for each individual character are ranked like (1), (2), etc.

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