Unlike Starro, I did decide to reach for Justice League of America villain Professor Ivo as an inductee in the original 90s Vile Menagerie. Like a lot of old school bad guys, Ivo didn't get a lot of play in the 80s and 90s, and it just so happened when he did, J'Onn J'Onzz was usually around. There was this one great panel of Manhunter hollerin' Ivo's name while smashing up his operation after the deaths of Vibe and Steel, but beyond that, Manhunter hasn't much tangled with Ivo directly.
Now, Manhunter's got his own evil professor, and he's already got enough foes whose names end in "o." Ivo hasn't proven much of a challenge on his own, while his creation Amazo is typically portrayed as too powerful for the Alien Atlas to handle alone. Ivo's more of a League foe, and the Menagerie hasn't need him in some time, so he's officially our first discharge. I mean, like Starro, he was beaten by Ice for God's sake! Still, here's his unedited entry from 1999/2000...
The ambitious Ivo has spent his life working toward nothing less than immortality, and along the way became one of the greatest inventors in history.
Young Anthony Ivo was traumatized by the death of his grandmother. At her graveside, Ivo vocally swore that he would never die. Anthony's self-centered reaction angered his father so much, that the usually gentle man backhanded his son into the open grave. Avoiding the grave became Ivo's singular concern. Playing on the guilt of his wealthy father, Ivo used every resource at his disposal to further his goals. In due time, Ivo created biomechanical mirror genes capable of scanning and imitating the genetic traits of a given subject. Ivo could salt his own D.N.A. with mirror genes, then absorb the properties of long lived species...if only he had the nerve to court death by putting theory into practice. Lacking intestinal fortitude, Ivo began pursuing other avenues to immortality. An elixir could be made by isolating common factors in creatures with notable longevity, but how could he procure such nigh-mythological beasts?
The debut of the Justice League of America inspired Ivo to create an artificial lifeform from his mirror genes. In need of raw genetic material for his creation, Ivo murdered volleyball player Helmut Schultz and his own father to form the brawn and brains of Amazo. The first Earth-born android, Amazo absorbed and duplicated all of the powers of the original JLA within it's mighty frame, in order to collect the beasts for Ivo's immortality formula. Ivo used Amazo to secure ancient objects of power and long-lived beasts, which enabled him to extend his longevity to 500 years. He also fought to gain the power of the JLA for himself, but his clashes with the team regularly ended in his defeat and incarceration.
Eventually, Ivo tired of the super-villain life, and retired to become a college professor at a small New England college under the alias "Ives". However, years of abusing his system with the immortality elixir caused Ivo's mind and body to deteriorate. Hideous scales formed at points over his flesh, and connected his nose to his chin. Ivo kidnapped several JLA members in a failed bid to restore his humanity, before being institutionalized at Arkham Asylum. Ivo escaped repeatedly, and continued working both on new Amazos, and on perfect artificial duplicates of himself from before his deformation. Over time, these duplicates became so disgusted by their creator's appearance and actions, they themselves committed him, then began to impersonate their master. The Ivos had inherited the original's madness, and began a series of assassination attempts that took the life of JLA member Vibe. The second hero to take the name Steel was paralyzed, and entered a coma from which he would never awaken. The Ivos reign of terror was ended by Ivo's longtime foe, the Martian Manhunter.
Ivo's immortality serum continued to mutate him, until he became so bloated and rigid, he was threatened with living an eternity as a immobile statue. In an attempt to find relief, he sent a fleet of "Amazoids" (duplicates of himself dressed as "men in black") to steal the powers of a number of top heroes. This led to another confrontation with the League. Capturing Ice, he revealed that he was so afraid of death, he abandoned his mother on her death bed. Now, with his scars turning as hard as steel, the fate he faces seems far worse even than the abyss. Ivo ordered the Amazoids to kill him with their stolen power, but he survived their blasts. Using Guy Gardner's power ring, Ice managed to whip up a cure for Ivo in JLQuarterly #5 (Winter '91). After Ice's death at the hands of the Overmaster, Ivo donated his base in the Carolinas to the Justice League Task Force, who used it's android inhabitants for training exercises.
Unfortunately, Ice was unable to free Ivo from his addiction to the immortality serum. He continued to abuse the substance, while creating more Amazos to combat Earth's heroes. After an unsuccessful attempt to create a traitor within the JLA (Tomorrow Woman, assisted by T.O.Morrow), he once again suffered from his serum's effects. Hospitalized in Aztek #10, Ivo was saved by his original, rogue Amazo. Even after making several attempts on it's creator's life previously, it admits, "...losing him would be like Tom losing Jerry."
Ivo is currently being held at Belle Reve Penitentiary in Louisiana.
Real Name: Anthony Ivo
Occupation: Mad scientist, former Professor of Astronomy
Group Affiliation: None; infrequent partner of T.O. Morrow
Base of Operations: Mobile
Known Relatives: Leonard (father, deceased), mother, grandmother (both deceased)
First Appearance: Brave & The Bold #30 (1961)
Weight: Unknown. Immortality formula causes extreme weight gain.
Hair: None. Formerly brown, then black
Powers & Distinguishing Features: As a result of his "immortality" serum, Ivo has developed a thick, resilient second skin. The skin appears to be bulletproof, and impenetrable to most forms of energy. The bulky, scaly mass impedes much of Ivo's movement.
Quote: "Yes! Keep that name at the forefront of your consciousness, Manhunter. Let it haunt you...Let it hound you--just as the Justice League has haunted and hounded me. One by one, Manhunter--I will murder the members of this Justice League--and, in so doing, hurt the original Justice League far more than a direct attack ever could."