Noncorporeal beings living in a dark matter nebula who feed on the neural energy of other species and possessed Voyager's crew to lure the ship back.
The Komar are noncorporeal beings found within a dark matter nebula in the Delta Quadrant. They sustain themselves by draining the neural energy of living beings, leaving their victims comatose.
In Cathexis, the Komar attacked Chakotay, separating his consciousness from his body, and then took over members of Voyager's crew one after another, including Tuvok, to steer the ship back toward the nebula's centre. Chakotay's own wandering consciousness worked against them by possessing crew members in turn, and Voyager eventually escaped once the Komar's influence was exposed.