However, in 1350 BC, Suppiluliuma I of Hatti attacked Mitanni and later waged war on the western side of the Euphrates.
In addition, a diplomatic game was played with Tutankhamen of Egypt to keep the Egyptians confused and out of the war.
I serve the king, my lord, but Biryawaza caused the loss of all [your] lan[ds.
He was initially considered a loyal ally of Egypt , before he joined the Hittites in an alliance under Aziru .
In the Amarna letters, Akhenaten describes him as a traitor, partisan and enemy of Egypt , with whom one would not sit at the same table .
In 1312 BC, he led a revolt against Hatti in the 10th year of the reign of Murshili II , but was murdered during the siege of Kadesh by the Hittites by his son Niqmaddu , who then assumed the kingship.