Mercurius (Earth-21)

The Negative Spirit is the sentient source of power of Larry Trainor.

Powers

 * Possession: The Negative Spirit was able to enter Larry Trainor's body and induce longevity in his body as well as keeping him alive for decades.
 * Radiation Production: The Negative Spirit is a radioactive energy source from outer space.
 * Electrokinesis: When outside of Larry's body, the Negative Spirit appears as a blue electricity silhouette, which is able to be used as an offensive attack.
 * Inter-Dimensional Travel: The Negative Spirit is able to bring Larry and the team to and away from the White Space.
 * Temperature Immunity: With the Negative Spirit in his body, Larry is able to withstand extreme heat and cold, as shown when he overcame experiments on his body after the accident.

Weaknesses

 * Bond to Larry Trainor: The Negative Spirit resides in Larry's body with no control over the latter's actions.
 * Nonverbal: Due to the Negative Spirit's status as an energy source, it cannot speak like a human being and can only communicate through Larry's hallucinations or physical contact.