Darko Brevic

 Darko Brevic' is the tertiary villain from GTA IV. Before the events of the game, he betrayed Niko Bellic's old army unit and got almost all of them killed. As a reward for Niko's services, Jon Gravelli and United Liberty Paper track down Darko in Romania. They kidnap him and bring him to Liberty City where Niko and his cousin Roman confront him. They discover that Darko is a drug addict and betrayed the unit for $1,000 to buy heroin. During the time that has passed, his addiction had worsened from his guilt. Darko states that Niko would be doing him a favor by killing him, and Roman tells Niko to let him live because he doesn't appear to be enjoying life too much. The player is then given the choice to either kill Darko or spare him. If Niko decides to kill him, he will shoot him 12 times (one for each death that he caused) and Darko will thank him with his dying breath. Niko will state that killing Darko did not make him feel any better. If Niko chooses to let Darko live, he will run away screaming and never be seen again. Niko will initially be angry at the decision, but he will then decide that killing Darko will accomplish nothing and that allowing him to live will be a worse punishment.