And now for a return to a favorite regularly scheduled universe building!
The Shadow Clan
When the Neo-Concordians ascended to become godlike beings, they shed their former existences as physical beings and left behind the raw detritus of their former selves. These godlike shells were the size of small continents and left to float in the blackness of the Shadow Dimension
that was created from the aftermath of their ascension. This dark dimension remained absent and filled with nothing but the rotting remains of cosmic powers long gone until Belial the Titan
realized their potential ability.
Guiding The Shadow King
to this place, he manipulated the defiant Anti-God into attempting to harness the power of the Neo-Concordians for himself. Unfortunately, this resulted in the deceased god shells developing a semblance of life, the undead beings driving off the Shadow King and seeking out the souls of individuals to fill their all consuming hunger. Thus were the Anti-Gods
Armed with their power, Belial proceeded to make a compact with the near-mindless omnipotent beings and began seeking out souls to feed to them. These souls would join with the Anti-Gods to comfort them in their twisted memories while their bodies would be filled with a "semblance" of a soul that would serve as their minions from that day on. The Shadow Clan is, presently, redistricted to Earth-0 because all of this didn't happen in some long forgotten epoch.
It all happened about two years ago.
The Shadow Clan are an alien invasion on Earth-0 that consists of Shadowmen
who are soulless individuals completely loyal to the Anti-Gods and eager to devour the souls of every human being on the planet. Shadowmen cannot feel emotion, pity, fear, or other feelings and possess a hive-mind that allows them to carry out their twisted duties. All of them possess the ability to use limited amount of shadow magic and can absorb the souls of a person to turn them into a Shadowman.
This is gross cheating of divine law as the souls of innocent mortals are being absorbed by the thousands and imprisoned in the Shadow Dimension irregardless of their mortal beliefs. This makes the realm very unstable but Belial doesn't care as he's attempting to use the power he's getting from them to destroy all of the Titans at once.
It may destroy much of the Nexus but he's quite sure it'll repair itself--eventually.
The Shadow Clan's members also possess the power to completely obliterate an individual. They can do this by absorbing them into the Shadow Dimension by sacrificing themselves. The result of this is everyone ceases to remember a subject in the world, their minds refusing to let them even consider they might have once been a vitally important part of the world. These subjects can, theoretically, be recovered from the Shadow Dimension but none have been so far.
Shadow Lynx is one of the few superheroes presently aware of them so far, most heroes unable to remember dealing with them due to their extensive magic. Mister Arcane is aware of them but underestimates their danger (his whole failed plural marriage and the resulting soap-opera distracted him--a fact he will beat himself up for years thereafter once the dust settles). Oddly, the world's magical girls are also aware of these individuals but they, Moonatic, and Pooka haven't been able to persuade people that "Kingdom Heart's villains are real!"
Leading the Shadowmen is the decidedly uncorrupted, Sun Tiger
. The androgynous "most beautiful being in the universe" possessed solar abilities capable of channeling metaphorical light as well as literal. Unable to succeed as a hero on his own, he had the Shadowmen murder everyone who remembered his failures and now serves as a mystical battery for their shadow magic summonings. Shadow Lynx has killed him on multiple occasions but Sun Tiger has always reformed since he is linked to the Anti-Gods. Worse, everyone forgets him and his crimes whenever he dies but her.
Sun Tiger is a somewhat "quirky" individual being a transvestite (though not transgender) being who impersonates a female superhero whenever not plotting the end of the world. Sun Tiger has attempted to join the Order on several occassions but is always blocked by Shadow Lynx. This is a major source of their rivalry.
That and Sun Tiger is a psychotic lunatic.