I am currently trying to translate the open-source game Widelands[1] into Latin. On the whole, I think I'm doing fine[2], considering I haven't tried to translate anything into Latin for the last five years, but for one word: One of their tribes is called "the Atlanteans" -- what would that be in Latin?

I tried to find examples and see whether I could see a pattern:
Athenae -- Atheniensis
Carthago -- Carthaginensis
Herculaneum -- Herculanensis
but also:
Neapolis -- Neapolitanus
Roma -- Romanus
Syracus -- Syracusanus

So... Atlantidensis? Atlantidianus? Atlantidines? Something else?
What would you suggest?



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[1] www.wl.widelands.org
[2] https://translations.launchpad.net/widelands