Gyeon Hwon Defects to Goryeo
Deposed by his eldest son Singeom and confined at Geumsansa, Gyeon Hwon escaped and went over to Goryeo.

Hangidan · CC BY-SA 4.0 · Source
When Gyeon Hwon chose his fourth son Geumgang as heir, the brothers Singeom, Yanggeom and Yonggeom staged a coup in the third month of 935, killed Geumgang and shut their father up in Geumsansa. Three months later he fled to Geumseong (Naju) and submitted to Goryeo; Wang Geon honoured him as sangbo and granted him Yangju as a fief.
The split in Later Baekje hastened Goryeo’s victory, and the next year Gyeon Hwon marched with the Goryeo army to Illicheon.