With Molon in most of the Seleucid kingdom and taking the title of king, Antiochus III stops a fight to conquer southern Syria from Egypt. Antiochus III instead marches against Molon, defeating and killing him and his brother Alexander on the far bank of the Tigris. Antiochus goes on conquer Atropatene, the north-western part of Media.
Meanwhile, the birth of a son to Antiochus III and Laodice leads Hermeias to think about getting rid of the king. This is to rule under the name of the infant son. Antiochus finds the plan and has Hermeias killed.
Antiochus III's commander in Anatolia, Achaeus, got back all the districts from Attalus of Pergamum. Hermeias said Antiochus III wanted to revolt. Achaeus takes the title of king and rules over the Anatolian parts of the Seleucid kingdom.