Full Name: Horton Everett Weaver
Appearances: Issues #1-6, 9-23, 26-28, 30, 36 and "Hearts and Minds."
In his first appearences, Butch was just Jenny's irritating older brother who gets turned into a monkey by the De-Evolutionaries. Over the years, he's, uh... matured somewhat (though apparently not when it comes to having his picture taken).
Butch is a normal human on our Earth and a monkey on Zot's Earth for reasons, as yet, not fully explained. When a number of the Devoes' victims were returned to human form in #16, the cure did not work on Butch. The conclusion reached, as Zot so scientifically put it, was that Butch had "just been a monkey too darn long."
Max gave Butch a metal belt in Issue #3 with red, blue and yellow buttons that each gave him temporary special powers, then took it back when the series went black and white.