- One of the two 'support lumes' added in the Road to Elysion DLC.
- Does not attack players or the core, but instead fires a 'mutating ball' which increases the rank of the lume it hits (adds a '+'), increasing their maximum health drastically, doubling the lume's current and maximum health on the first mutation. The second mutation raises it to a total of three times its original health, then four and so on.
- Mutators amongst light enemies tend not to be much of a threat, but mutators near heavier enemies can easily be the difference between success and failure. It can be useful to leave enemies on low health so that mutations are wasted increasing their health slightly rather than on something with more health.
- There is a fixed delay between each time it fires its mutating ball before it can fire again.
- The mutating ball has 1hp and can be destroyed with any weapon. Weapons with an area of effect tend to be very effective at this, particularly the ETK-Tesla Prototype primary fire.
- If left unattended, mutators have the time to fire several mutating balls, creating high-rank lumes which prove extremely difficult to kill.
- Mutators will not run towards the core, instead they will try to run towards a random lume between each mutation attempt, once they recharge, they will try to fire it at any lume currently in range. This results in an erratic, unpredictable movement pattern.
- Their weak point is the small "Eye" towards the lower half of their body at the front, this can prove very difficult to hit consistently given the above point.
- Mutators will never target other mutators, themselves or Healers. Similarly, Healers will ignore them.
- If all lumes in a wave except Healers and Mutators are killed, any surviving mutators will self-destruct.
- Weapons with crowd control capacities such as REX, Gatling Laser secondary fire and the Ballista secondary fire works well damaging Mutators without the need to close distance putting the player at harm's way against aggressive lumes.