Updated for IR 1.4.2

Possibly.
I found the modding of this game very frustrating even for such a simple mod.

There's quite a few big versions released for the game since I last played, and, who knows, maybe it's better now.
I will try to spend a few hours in the following weeks to see what can be done, but I'm not going to do any new features/additions until I will actually play the game (as I'm unfamiliar with the current game mechanics and features, I can't really change them, lol)

Any chance you might update this mod? I would love to use it, as Paradox's culture groups irritates me a lot.

I'm on the fence about the name of the God. There are many variants for the name and it is uncertain which, if any, is the correct written form of the name.
I chose Zamolxis only because it's one of the most quoted forms and it's also close to the modern romanian (dacian descendants) name for it (Zamolxe)

But I might remove this change. Right now it doesn't seem to be working. No matter how much I try, none of the custom localisations don't work at all in any mod. I created localisation mods the same way for CK2 and Stellaris and they work fine there, so I guess it's a game bug.

And regarding the thracian and dacian cultures - I really don't understand why they weren't in the same group to begin with.
Eventually I will try to rename the group to Thracian.

Why Zamolxis? The genuine form is Zalmoxis. There are so many composites like Zalmodegikos, Zelmutas, Zelmis, Zelmos, Selmios. There are no Thracian onomastics that imply "Zamolxis" - it was Strabo's metathesis.

Other than that great idea for a mod and thanks! Nice to see Thracia put in the Dacian group.