Tyson Rios/Elliott Salem (Army of Two: The 40th Day)
Army of Two: The 40th Day features two tight-as-brothers protagonists who blast their way through the streets of Shanghai. They bond as they try to stop Jonah Wade from annihilating the city. When the two confront Wade at the end of the game, the villain gives them a choice. They can either shoot Wade, an act Wade claims will doom Shanghai to nuclear annihilation, or one can kill the other in exchange for the lives of the people of the city. If you choose to kill your partner, YOU are number 10 on this list.