Guest blog: 5 Games that implement great Karma Systems

Infamous 2:

This game was developed by Sucker Punch Productions. Every action of the main character in Infamous affects Cole, the main character in some way. This is a popular and common title when talking about Karma systems.
Knights of the Old Republic
This RPG takes place within the Star Wars world and essentially gives the player different dialogue opportunities based on the choices of the character. Often the dialogue is presented as lengthy options after the conversation is over. BioWare, the developer, tends to make games from two perspectives: good and bad, and you can choose how to experience the story.

Mass Effect:

Mass Effect is another game developed by BioWare with a karma system similar to Knights of the old republic. However, the interaction during dialogue sequences was revamped to give a more cinematic feel. Interactions with NPCs feel less scripted.

Fallout 3:

A game developed by Bethesda Game Studios, takes the karma system in a new direction (although the system is actually referred to as Karma, in game). In addition to affecting the dialogue options, the choices a player makes have tangible effects on the player. For example, some abilities in the game require different levels of karma to obtain.

Fable:

Developed by Lionhead Studios, Fable offers a few unique twists to karma systems. Alignment is a major part of the game. The food you eat and the way you treat NPCs affects your alignment and your reputation. Further, your alignment affects your appearance. Play as a wholesome, do-gooder and your character appears bight and even sports a halo. Play as an evil, murdering goon and your appearance is dark and pale and your experience is increased at night.
On the other hand, the Grand Theft Auto series has a pathetic karma system. Get far enough away from the police, for example, and they’ll forget you just murdered an innocent pedestrian.