 This deepening compromise with Spain led Cotabato to its downfall.Fearing Buayan's reemerging power, Sultan Kudarat II finally ceded Cotabato to Spain in return for an annual pension of 1,000 pesos for him, and 800 pesos for his son.Buayan, under Datu Uto, had, by the 1860s, become the power of Maguindanao.