Complex sentence: The head of the tribe finding about their affair had their house burned to ashes, the "Bakunawa" finding out about this became immersed in anger and tried to take revenge by eating all the 12 moons.
Split into simpler sentences: The head of the tribe found out about their affair and had their house burned to ashes. The "Bakunawa", finding out about this, became immersed in anger and tried to take revenge by eating all the 12 moons.