The Plazmite has a special ability to store and release thermal energy at will. Theese insects is attracted to heat sources, which they thrive on. They are also carnivorous, however, and fly up and down hallways searching for prey. If a Plazmite feels threatened, it will fly towards its enemy and release thermal energy bursts at it until the threat is dealt with. This feeling is usually triggered by being hit by a Beam weapon or if one is fired near its zone of comfort. When destroyed, the areas they once lit up become dark.
- Though their name seems to be a portmanteau of "plasma" and "mite," Plazmites are more closely related to real-world fireflies.