Akbuzat

Akbuzat (Bashkir: Аҡбуҙат, from Ak is "white" + Turkic буҙат "Curly Horse") is the most famous kubair (epic poem) of the Bashkirs. It is analog many similar epics (the Pegasus).

The main hero of Akbuzat epic poem is Hauban. He went to the Underwater kingdom for search the сurly horse Akbuzat and diamond sword.

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Wikipedia