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Ancient civilization of the Mordebi. It was presumably decimated during The Breaking, reducing the Mordebi to warring clans and nomads.
"Tehatamani" may have been the name of the capital city of the ancient empire. The ruins of the city (or what is left of it) can be seen in the "Temple of Tehatamani" zone, southwest of Ahgram along Qalia's south coast.