Leila Davis was married to Anthony Davis, the Ringer. Abner Jenkins, the Beetle, coerced him into attacking Spider-Man, who easily defeated him. Sometime after that the Ringer found himself in the Bar With No Name and was one of the nineteen villains gunned down by the Scourge of the Underworld.
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Leila sought revenge on those that she blamed for her husbands demise. Spider-Man, The Beetle & Scourge. She inserted herself into Abner's Sinister Syndicate posing as Boomerang's girlfriend and later Speed Demon's when Boomerang was captured. When Abner's guard was down, she aligned herself with the Rhino and Boomerang in attempt to kill Jenkins using her husband's weapons. The battle was stopped by Spider-Man and the entire group was arrested.
Leila was later paroled and she immediately formed a new group with the intention of continuing where she left off. Donning a power armor, she dubbed herself Hardshell. It was during this time that Anthony Davis revealed to her that he was still alive. Apparently AIM found him at the Bar With No Name and he was barely alive. They managed to save his life by turning him into the cyborg Strikeback.
Leila abandoned her team and left with her husband, the sole reason she was a villain. Some time later Anthony's cybernetic systems failed and he finally died. On his deathbed he requested his wife become something better and after he died Leila turned herself over to the government. She was given, ironically, the Beetle Mark III battle suit to wear and joined the government's Redeemers. Luck however was not on Leila's side as after two missions the team was sent to fight Graviton. She was killed when he used his powers to crush the armor with her inside of it.