apparently Mamai's wife, the daughter of Khan Berdi Beg. Meanwhile, Mamai's Crimean headquarters already coined in the name of Muhammad-Sultan. After suppressing opposition in Volga Bulgaria with the help of Dmitrij of Suzdal', Mamai felt secure enough to proclaim Muhammad-Sultan khan at Sarai the end of 1371 or the beginning of 1372.

Mamai's success once again proved ephemeral. Perhaps during Mamai's absence, in 1373, Sarai attracted a new conqueror, Urus Khan,