One of the last things I noticed when played the Mass Effect games was that it broke my definition of “role-playing game.” This is a definition that has worked for me for well over a decade. I can, using it, effectively separate controversial games from one another. Mass Effect was the first challenge my RPG definition (see below) has had to face.
The biggest thing most people seem to have noticed when playing Mass Effect 1 or 2 is the moral decision-making process. This mechanic, so common to role-playing games since Fallout and early BioWare and Obsidian games, was suddenly injected into a much different style of game, a cover-based science fiction shooter. It helps that Mass Effect is arguably the best example of the form: the Renegade/Paradox division flows naturally from the game’s setting, and the writers and voice actors are both in fine form throughout both games.