Guys, just name the game you are going to spoil and then cover the actual betray in spoiler tags. So far I have been lucky of playing all these games shown here, but imagine just...running across something you wouldn't like to see!
For me:
Knights of the Old Republic:
Malak's betrayal, which incidentally set the events of the whole game in motion.
Metal Gear Solid 1, Metal Gear Solid 2, Metal Gear Solid 3, Metal Gear Solid 4 and you can bet your ass Metal Gear Solid 5:
Revolver Ocelot. Seriously, do I have to dwellve on this one?
Dead Rising 2: Off the Record:
Stacey, in exchange of Sullivan. Such an unexpected move. Well done, Capcom, well done.
Tales of Vesperia/Tales of Xillia:
I put these two games together since Raven and Alvin cover pretty much the same character scheme, and they pretty much fuck up the party throughout the events of their respective games.
Metro: Last Light:
Being stabbed in the back by Pavel. I didn't, however, feel angry at him as it is later revealed in the game that he did not want to sacrifice their friendship but his bond to his group of comrades was too strong. Then, later, you can chose to forgive him, leaving with the impression that they both share a common, strong bond too.
Dragon's Dogma:
Edmun Dragonsbane. Seriously, fuck off asshole.
I could probably think of more later.
