The Mass Effect Trilogy is a series of action role-playing video games developed by BioWare. It follows the story of Commander Shepard, a human soldier tasked with saving the galaxy from an ancient alien race known as the Reapers. Players make choices that affect the narrative and relationships with various characters, including species like the Asari, Turians, and Krogans. The trilogy consists of three main titles: Mass Effect, Mass Effect 2, and Mass Effect 3. Each game builds on the previous one, featuring improved gameplay mechanics and deeper storytelling. The series is known for its rich lore, character development, and the impact of player decisions on the game's outcome.