Remnant engines are exclusively sold by the Remnant, and can be unlocked along with the rest of their outfits by completing a series of missions for them. They are supposedly based on human ion engines, but they share plenty more features with plasma engines instead, including even the plasma engine sound.

Remnant engines are characterized by their considerable energy drain, but make up for it by producing relatively little heat, and are very space efficient. In the big scope, they drain a little more energy than, for example, Korath engines, but produce twice as less heat, though they are a bit less space efficient.