Saturnyne has a Machiavellian mind, indomitable will, and is a cunning strategist. She prefers to let others fight for her, but is not afraid to get her hands dirty if the need arises; she knows an unspecified martial art, and is a capable shot, with access to a wide range of advanced weapons. As Majestrix, she commands the Avant Guard and the Corps. The Guard are either non-human or from a highly evolved Earth, possessing minds “like oceans,” resistant to psychic powers. They are commonly garbed as businessmen to blend in, with umbrellas that fire de-evolutionary rays, energy bolts, or warp beams to send targets on one-way trips to hostile dimensions; this technology also allows them to teleport between realities. The Corps possess a wide variety of superhuman powers, most commonly flight, superhuman strength and force fields.
Opal Luna Saturnyne was born on Earth-9, but, at an unspecified point, she relocated to the high-tech Earth-522, location of the Hub, base of the Dimensional Development Court, who maintained order throughout the dimensional planes. The DDC was undertaking a 50,000-year program to upgrade the “Earth series,” and monitored alternate Earths’ progress to ensure that problems in one reality did not have a detrimental effect on the others. Through a combination of ability and insuperable perseverance, Saturnyne rose to become Omniversal Majestrix, the Hub’s ruler and the DDC’s nominal head — the DDC’s true master being the Omniversal Guardian Merlyn, though given Saturnyne’s apparent belief she was in charge, it appears that the manipulative Merlyn either kept his control secret or else permitted the DDC much autonomy.
On Earth-238, the powerful but insane reality-warping mutant Sir James Jaspers, aka Mad Jim Jaspers, had taken over Britain, turning it into a fascist state, and using his enforcers the Status Crew and the hero-killing cybiote Fury to slaughter the entire planet’s superhuman population. The DDC identified Earth-238 as retrograde, holding all the others back from entering a scheduled new era of reason, peace and enlightenment; keeping the problem’s true cause secret, Merlyn sent Saturnyne there, ostensibly to administer an evolutionary push. Accompanied by her Avant Guard and assistant Dimples, Saturnyne covertly set up base under London, and spent at least six months preparing for “the Push,” testing the evolution-accelerating “life enhancing fluid” on local life-forms, and preparing to distribute the fluid via the country’s reservoirs. Merlyn sent one of his interdimensional Corps, Earth-616’s Captain Britain (Brian Braddock), and Braddock’s Otherworld elf companion Jackdaw to 238, needing Braddock to encounter the Fury and Jaspers as part of a larger plan to stop Jasper’s more dangerous 616 counterpart. A life enhancing fluid leak created the mechanical Junkheap that Walked Like a Man, which rampaged across London, drawing both Braddock and the Status Crew’s attention. Braddock destroyed the Junkheap, and traced the fluid that had created it back to Saturnyne’s base, but after initially battling her Guard, he assisted them when the Status Crew attacked. During the ensuing fight Captain Britain and Saturnyne saved one another’s lives, and afterwards he agreed to aid Saturnyne; though she and the Captain shared an unspoken mutual attraction, neither acted on it. With his help, the initial Push was successful, but then Jaspers plunged 238 into a chaotic reality storm. The Status Crew unleashed the Fury on the otherdimensional visitors; swiftly learning her Guard’s weapons could not harm the cybiote, and with 238 lost to madness, Saturnyne cut her losses, ordering her Guard to warp back to the Hub, abandoning Dimples, Jackdaw and Captain Britain to be slain by the Fury.
The DDC placed Saturnyne on trial for the disaster, with her ambitious successor Mandragon serving both as judge and prosecution. He barred the Avant Guard from giving testimony, so Saturnyne hired Gallifreyan parahuman interdimensional mercenaries, the Special Executive, to kidnap Captain Britain from Earth-616 (where he had been returned after Merlyn resurrected him, following his death on 238) as a defense witness. At Saturnyne’s show trial, Mandragon destroyed Reality-238, ostensibly to prevent the warp spreading across the entire multiverse, but really to eliminate any evidence that might prove her innocence; he also provoked Brian into making a rash outburst, so that the bailiffs restrained him, making him ineligible to testify. Mandragon ruled Saturnyne guilty and sentenced her to immediate execution. Assisted by the Executive, Brian freed Saturnyne and the group fled back to Earth-616, taking refuge at Brian’s home, Braddock Manor. Linda McQuillan, formerly Earth-238’s Captain UK, who had escaped to 616 during 238’s hero purge, soon warned them that 616’s Jaspers had begun his rise to power. However, McQuillan was followed by the Fury, which had survived its reality’s destruction and come hunting the prey that had evaded it. Despite heavy losses, the combined heroes temporarily neutralized the Fury, but Saturnyne convinced the reluctant Brian that they needed to find another hideout. Saturnyne, Brian, the traumatized Linda, and the manor’s other inhabitants — Brian’s telepathic sister Betsy and her two fellow psis Tom Lennox and Alison Double — headed to London.
Distorting time, Jaspers rapidly became prime minister and had armored agents round up the country’s superhumans. Captain Britain set off to confront Jaspers, but in his absence troops raided the hideout; Lennox was slain, while Betsy and Alison were restrained. Saturnyne tried to convince the terrified Linda to stay and fight, but when she fled, Saturnyne reluctantly followed, leaving the other women. Catching up with Linda, Saturnyne castigated her and struck her, deliberately provoking Linda until she lashed out, breaking her out of her funk, then browbeat Linda into donning her Captain UK costume. Hoping to assist Brian, the pair arrived at the prime minister’s Downing Street residence in time to witness the Fury, which had followed Brian there, slay Jaspers; Brian and Linda together then destroyed the weakened hero-killer. While the two battered heroes comforted one another, Saturnyne covertly took skin samples from Jaspers’ corpse; seconds later they were teleported to Otherworld, where they learned from Merlyn’s daughter Roma that her father had seemingly died; Roma also secretly killed the cells in Saturnyne’s sample. After the trio attended Merlyn’s state funeral, Saturnyne returned to the Hub, where, unaware her threat was an empty one, she blackmailed Mandragon into reinstating her as Majestrix, lest she unleash a Jaspers clone on his world.
Though Roma secretly observed this exchange with amusement, having replaced her father as Omniversal Guardian, she determined it best to keep a closer eye on Saturnyne. Quietly discontent with being under another’s dominion, Saturnyne nevertheless acquiesced to obeying Roma, believing she could not resist, as she was mortal and Roma a god. She split her time between Otherworld and the Hub, and with Saturnyne’s naturally frosty, superior façade, Roma played “good cop” to Saturnyne’s “bad cop” while carrying out various manipulative schemes. Under Roma’s order, Saturnyne sent Gatecrasher’s Technet to pursue Phoenix (Rachel Summers), triggering Excalibur’s formation; later, when Excalibur were dimensionally displaced, Saturnyne brought them to the Hub, taking amusement in deliberately flirting with Brian to provoke the obvious jealousy of Brian’s new girlfriend, the empathic shapeshifter Meggan Puceanu, before returning them home. She subsequently sent agents Horatio Cringebottom and Bert to remove Excalibur member Widget’s dimension-hopping powers, timing their arrival to help Excalibur gain the upper hand in a battle against the Technet, and intervened to stop the Corps from trying Brian for breaching membership regulations — though she coldly informed him she was merely obeying Roma’s instructions to do so when he tried to thank her. Brian returned the insult soon after, when he invaded Roma’s Starlight Citadel to confront the Guardian for manipulating him; Saturnyne came to Roma’s defense, only for Roma to rebuke her for exceeding her authority, and Brian to curtly dismiss her, telling her to do as she was told and keep quiet, since he was talking to her boss. Shortly after this, Saturnyne was present when Merlyn revealed his death had been a ruse, and she later attended Brian’s wedding to Meggan on Otherworld; at the reception she admitted to him that she had secretly believed she was the one he might marry and made a pass, which, to her annoyance, he immediately rejected.
Roma, judging Franklin Richards-616’s reality manipulating powers a danger, ordered him brought to Otherworld, and Saturnyne dispatched the Technet to kidnap Franklin, which in turn drew his family, the Fantastic Four to Otherworld; after coming to an agreement with Roma, they returned to Earth-616, with Corps member Caledonia joining their household. When Dr. Doom-616 subsequently sought to overthrow Roma during an interdimensional crisis precipitated by a faulty Cosmic Cube, Saturnyne was briefly imprisoned and impersonated by her dimensional counterpart Sat-Yr9, but soon escaped and overpowered her doppelganger. She was later present during the Abraxas crisis and was on Otherworld when Dimension-616 was engulfed in the Scarlet Witch’s “House of M” reality warp. As with the Cube crisis, Saturnyne showed little hesitation in suggesting destroying 616 to prevent the warp spreading, memories of the horrors of the two Jaspers’ warps she had endured all too vivid. Brian, who had been crowned Otherworld’s new ruler (and thus head of the Corps) by Roma, returned to Earth-616 to ensure the warp did not destabilize the entire Omniverse, and remained there once the threat ended; in his absence, Roma resumed rule, but made Saturnyne the Corps’ operational commander. The Witch’s warp had the unfortunate side effect of resurrecting Jaspers; egged on by a temporarily insane Merlyn, he attacked Otherworld, turning many of its defenders into Fury facsimiles. Joining the battle, Saturnyne nearly slew Jaspers with a gun designed to rip his soul from his body, until forced to halt her assault to drive back attacking Furys; while she was away from Roma’s side, Merlyn apparently murdered his daughter. Though Jaspers was eventually stopped, the Corps was nearly annihilated; Saturnyne, assuming command, chose Brian’s more militant counterpart, Reality-70518’s Albion (Bran Bardic), to rebuild and lead the Corps, telling Brian that with the battles she believed were to come, the Corps needed a full-time, harder leader, while Brian was better suited to keep an eye on things on his homeworld, which had spawned several interdimensional threats.