Bio: Nothing is known about how Lassiter joined the Cartel or any of his dealings with their group prior to their first battle with the Avengers.
In order to take down the Zodiac Cartel Nick Fury, disguised as Scorpio captured the Avengers. He called the Cartel for a meeting in order to present the Avengers to them. The Avengers managed to break free before the Cartel could execute them. Fury nmasked himself and joined the heroes in fighting off the Zodiac Cartel. Aries managed to claim the Zodiac Key, and led the Cartel to their escape through a hole in the wall.
Lassiter led the reorganization of the Cartel and its planning to takeover Manhattan. A mercenary group in the Zodiac's employ was sent to Avengers Mansion and was able to subdue the Avengers who were subsequently put into stasis. The Aries-led Zodiac army was able to take over Manhattan. Aries used the Zodiac Key to entrapping it within a force field. The Cartel demanded one billion dollars or they threatened to kill the entire population of Manhattan. The Black Panther and Daredevil managed to free the Avengers, and, in the ensuing battle, Aries was apparently slain Thor destroyed his vessel with a bolt of lightning. The rest of the Zodiac Cartel escaped capture.