Visayas actually split during the revolution there is a Visayas republic during that time, so a split is possible.
All headed by Tagalogs, or people who wanted to side with them.
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But okay, never mind, I'm making my biases far too clear here. As is kasumigenx.
So.... worst case scenario, the Philippines is divided into 4 or 5 countries used as puppets against one another in European proxy wars: Maguindanao, Sulu, the Free City of Zamboanga, the Tagalog Republic in Luzon, and the Republic of the Philippines in Visayas.