Mass Effect is an action RPG and the first game in a space trilogy by developer BioWare. While comparisons may be made to their previous Star Wars: Knights of the Old Republic games, Mass Effect gives the player more control over combat and is set in an original universe. Some of the races populating this universe are blue-skinned Asari, synthetic-killing machines called Geth, and large saurian warriors known as Krogan.
During the game you play as Commander Shepard, the first human chosen as an elite S.P.E.C.T.R.E. agent, tasked with investigating an ancient Prothean artifact on the planet Eden Prime. The game plays as a third-person shooter with the ability to pause combat and use the special abilities of both Shepard and squad members (all of which you can level up). As the game progresses you will also collect new weapons and armor to upgrade your squad, and new members will join you on your quest. The game features numerous dialog options, but uses a reactionary system where the player merely chooses what type of response they want without seeing the actual dialog choices. In order to maintain a cinematic experience BioWare chose to voice the main character as well as all NPCs, unusual for a game with such heavy RPG elements.
From the game box:
An ancient threat returns.
One final hope emerges.
As commander Shepard, you lead an elite squad on a heroic, action-packed adventure throughout the galaxy. Discover the imminent danger from an ancient threat and battle the traitorous Saren and his deadly army to save civilization. The fate of all life depends on your actions!