Any great video game story will be littered with compelling and complex personalities.
It's crucial to maintain strong character development throughout to make players truly care about the quest they are undertaking. Boring characters means a pointless plot, but when they are used to create a shocking twist, it can justify their existence tenfold as it becomes clear that they were only there as a narrative device.
If a betrayal is weaved into a story in a way that makes sense, with small and subtle hints given along the way, it will stick in players' minds for years to come.
There are plenty of films, books and TV shows that take advantage of the story potential that a good betrayal can provide, and as the writing in games only gets better as the years roll by, they're becoming increasingly more evident in the medium.
Some are telegraphed from mile away, but others truly take players by surprise even when there's foreshadowing around every corner. Turning the story on its head, a character's unapologetic betrayal of the good guy can be so very satisfying.
10. Mark Jefferson - Life is Strange
Life is Strange released in 2015 to much critical acclaim thanks to its fantastic storytelling and intriguing character relationships. Max Caulfield's experiences at Blackwell Academy in Arcadia Bay, Oregon stayed in the minds of players for a while after the credits roll, but that's not to say there weren't some head-scratching moments.
One such example is the game's main antagonist, Mark Jefferson. The photography teacher at the school and often serving as a confidant for Max, Jefferson spends much of his time manipulating, drugging and, in some cases, murdering the students to further his own artistic ventures. His dubious alliance with Nathan Prescott and indirect association with Rachel Amber's death are just the tip of the iceberg.
He's only revealed as the bad guy in the latter stages of Chapter 4, and because he's not one of the narrative's main characters it feels so very out of the blue when his crimes become known. There's no foreshadowing, so when one of Max' biggest influences becomes Max' biggest nightmare, the betrayal feels almost too sudden.
In true Life is Strange fashion, though, later games would adopt a similar, puzzling narrative wrinkle and it still makes no real sense.