WARNING: The following contains spoilers for Iron Man #1 by Christopher Cantwell, CAFU, Frank D'Armata and VC's Joe Caramagna, on sale now.
Iron Man is is going retro in his new series, in more ways than one. Tony Stark has dumped his company, and bought a classic car and a brownstone in New York City, where he wants to get back to the basics. He's replaced his super-tech armor with a regular suit that he puts on piece-by-piece, which Hellcat refers to as "vintage." Then Iron Man and Hellcat teamed up to fight a classic villain.
The heroes were out, taking a "jaunt through the Big Apple," when they found a helicopter on top of the library, which seemed odd. When they went to check out the closed library, they found a villain leaving with a book. This villain was Unicorn, which both heroes reacted to in a puzzled manner. However, when they approached him, he said he only serves "the other," who he calls a "monotheistic God." When Unicorn tried to escape, Iron Man brought the helicopter down and confiscated the book, which turned out to be a Gutenberg Bible. Sadly, lightning struck Iron Man, destroying the rare book.
Unicorn debuted in 1964, in Stan Lee and Don Heck's Tales of Suspense #56, where he battled Iron Man. Unicorn attacked Stark Industries in that issue, beat up Happy Hogan, and kidnapped Pepper Potts. This incident put him directly in the crosshairs of Iron Man. It turned out that The Unicorn was similar to many other villains of that era. He was a Soviet villain trained behind the Iron Curtain using a power horn Crimson Dynamo created before defecting. This horn allowed him to project energy rays and shield himself from attacks.
Unicorn proved his mettle in Iron Man #1, as he used his energy ray to blast Hellcat out of the fight. He then used the energy shield to blow Iron Man off his back. Unicorn only fell in battle because he tried to run, and Iron Man shot down his helicopter. However, he has never been more than a B-list villain, with very limited appearances.
Unicorn disappeared for a long time and ended up with his mind experimented on, which made him a little "weird." This treatment left him with superhuman strength but accelerated aging, forcing him through many attempts to find a cure. From the Red Ghost to The Mandarin to Titanium Man, Unicorn went from villain to villain, trying to cure himself. His enemy, Iron Man, finally cured him, but it drove Unicorn insane.
Aside from appearing in Frank Tieri and Al Barrionuevo's Infinity: Heist in 2013, Unicorn has not had any major appearances in the last six years. But now, it is clear that the villain still suffers from mental instability and is now in service to a new master.