According to Ibn Ardashir, after capturing Osmancık Bayezid was joined by Ahmed Bey of Amasya, Mahmud Çelebi and Kilic Arslan, the heirs to the Beylik of Tacettin that Burhan al-Din had occupied, the Taşanoğlu rulers of Merzifon, and other local chieftains.[15] Even more flocked to Bayezid after the latter captured the fortress of Kırkdilim from its Kuvvaddaroğlu ruler, Saydi Mahmud.[15] Manuel does not report these events, perhaps because the operation to capture Kırkdilim was not especially difficult.[16] Ibn Ardashir in turn claims that Burhan al-Din took position on the plain of Çorumlu, from where he issued challenges to battle.