LogFAQs > #908058553

Persona 5 - Shido having Akechi, the SIU director, and Okumura killed.
Final Fantasy VII - Hojo and Sephiroth betray Shinra. And given that Rufus actually survives Heidegger and Scarlet might be mentioned as well. Forget what they were going for but theres something on the lines of "Who cares? The president is dead!" said. Which implies it would not be okay with Rufus nor that they were even going to try to save him.
Final Fantasy IX - Kuja betrays and effectively kills Brahne and Garland.
Final Fantasy X - Seymour killing Kinoc.
Final Fantasy XII - Gabranth and Drace(She tries at least) betray Vayne.
Final Fantasy XIII - Barthandelus kills Jihl.
Far Cry 4 - Pagan effectively gets Yuma killed and she was also going to betray him iirc.
Prototype 2 - Mercer consuming Sabrina and Sabrina selling out Roland? Rolance? Something like that.
For Honor - Holden betrays Apollyon.
Dragon Age Inquisition - Solas kills Flemeth? Flemeth posesses Solas? Havent done the final dlc but someone betrays someone in some way or another.
Kingdom Hearts II - Axel more or less defects from OXIII and Roxas was about to?
God of War 2018 - Kind of. Thor doesnt really make an appearance but is heavily implied he will be a villain at some point and he beats Modi half to death offscreen.
Kingdom Hearts BBS - Kind of. He doesnt succeed but Vanitas attempts to kill Ventus which would count as betrayal to Xehanort.
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