Midnight Marauders: Doctor Gordon Meet Doctor McNider

Two doctors scarred by tragedy, claimed by the night, casting long shadows of legacy. Doctor Bruce Gordon and Doctor Charles McNider were geniuses in the field of light, mastering it despite being impaced by disabilities that led to their costumed careers. One was a craven criminal, the other a courageous crimefighter.

Doctor Bruce Gordon was infected while visiting a South Pacific Diablo Island. There he confronted a misguided local priest named Mophir, who cut the doctor's flesh with a black diamond before perishing to his death. This infection caused Gordon to transfer him into an evil persona of himself named Eclipso during each eclipse, whether a natural or an artificial one. This led to a new supervillain who terrorized the world, opposed by his alter ego.

Doctor Charles McNider sustained permanent injury to his optical nerves following an explosion during a surgical procedure he was performing. After this, he learned that he had the ability to see in darkness when an owl crashed through his home's window. Devising infra-red goggles allowing him to see in daylight, while his own vision adapted to grant him sight in total darkness, Charles developed weaponry for his costumed career as Doctor Mid-Nite. 

Utilzing the black diamond as a weapon, Eclipso could cast frezzing darkness when positioning the dimaond in front of his eclipsed left-side eye, while emit devastating beams of light when cast over his normal right-side eye. To combat his adversarial alias, Bruce equipped his friend (and later himself when he and Eclipso separated into two individuals for brief periods) used light flash grenades and ulta-violet weapons to revert the villain back to his domant state within Gordon's body.

In addition to the Doctor's grenades which caused the blackout mist, he later devised a cryotuber that shot devastating laser beams, freeze rays and paralysis fields. This device was instrumental in some of his adventures during the 1960s, although he later retired his cryotuber for some unknown reason.

Interestingly, during a teamup between the Justice League and Justice Society, an alien entity known as Creator2 led his minions into battle versus the Society in order to obtain Earth-Two. This malefactor's plan was to destroy that world, paving the way for another to replace it. As each of his henchmen attacked individual members of the Society, one cornered and captured Doctor Mid-Nite in a specialized immobilization net. As had happened with the Doctor's teammates Superman and the Flash, who likewise were captured which inadvertently caused their Earth-One doppelgängers to also be paralyzed in their own universe, a similar thing happened with the Doctor. However, in this instance, it was Mid-Nite's "closest Earth-One equivalent" the Batman who felt the effects. Why not Eclipso?

In an earlier tale, Batman confronted Eclipso several stories outside a skyscapper. However, a flash light grenade employed by Bruce Gordon below the two men caused Eclipso to revert to his phantom form, which passed down through Batman below him, before reentering Gordon's body. This caused a portion of Eclipso's aura to surround Batman, in place of the aura originally around the superhero before he brought it to life to combat Doctor Double X (which caused the aura to cease to exist after that tale). 

Simultaneous to Creator2's invasion occuring on Earth-Two, Doctor Gordon had sent Eclipso and himself to another dimension outsiding Earth-One's universe, seeking to rid his world of his menacing alter ego. Hence, Doctor Gordon was not on Earth-One when Doctor McNider on Earth-Two was immobilized... leading to the the person most connected with Eclipso being Batman himself!

The counterpart of Doctor McNider's nurse and girlfriend Myra Mason was a future Myra Mason who assisted industrialist Rick Starr in both his business and costumed identities. This Myra was aware of Starr's alter ego as Space Ranger, and aided him on various adventures in the 22nd century of Earth-One, while the Myra Mason of Earth-Two never seemed to connect the dots between her boss and boyfriend, and his masked manhunter alter ego, even when she played the role of a female Doctor Mid-Nite alongside other girlfriends of Mid-Nite's Justice Society of America.

* Apparently, Wonder Woman’s purple ray also gave Doctor Mid-Nite extended youth and longevity matching that of his Justice Society  teammates, who had their own lives extended by exposure to Ian Karkull’s radiation years earlier.

** Since the aura-duplicate of Batman self-destructed following his victory over Doctor Double X, this left a void around Batman later filled by the chronal-energy aura of a time-traveling Enemy Ace. Von Hammer had been drawn to Batman’s time and used as a pawn by the Lord of Time versus Batman’s Justice League and Doctor Mid-Nite’s Justice Society.