The Megazone has historically, and incorrectly, also been called the Hydra. This name confusion starts with Jerry Sewell defecting to Mighty Mite to make “Megazone” bodies. Jerry may have invented the “Hydra” body. Later, Sandoval made revisions and later called it the “Megazone.” In any case, the Hydra is an entirely different guitar body (see pics below).
Jerry and Grover Jackson were childhood friends. Grover brought Jerry into Charvel after he started working there. After Grover bought Charvel from Wayne and was making bodies for Mighty Mite, Jerry defected to Mighty Mite. Jerry copied the templates and was given a wood shop to run at Mighty Mite and cut Grover out.