The Darkness At The Edge Of The Galaxy
From the Mass Effect Wikia: "Biotics is the ability for some lifeforms to create mass effect fields using Element Zero nodules embedded in body tissues. These powers are accessed and augmented by using bio-amps. Biotic individuals can knock enemies over from a distance, lift them into the air, generate gravitational vortices to tear obstacles or enemies apart, or create protective barriers. "
Biotic come in a variety of forms (List Biotic powers here). Biotics are extremely dangerous, and combinations can detonate in massive explosions.