Zzzax is one of the enemies of The Incredible Hulk. Essentially a giant lightning bolt, Zzzax made his shocking debut in The Incredible Hulk #166 (first published August 1973). After a group of terrorists broke into an atomic lab and threw some bombs, a new weird fusion of energy appeared, swallowing three of the men whole. The new energy formed into Zzzax, who claimed to feed on the electrical energy of the human brain.

Zzzax escaped from the lab and began attacking people. Mild-mannered Bruce Banner, seeing the commotion, went to confront the beast, who knocked out Bruce and almost zapped his brain for energy, when out of the blue, Hawkeye showed up and distracted the creature. Bruce awoke and - well, you know what happened then! So The Hulk and Hawkeye square off against the giant electron, and finally after some minor scuffling, Hawkeye figured out that the creature was in fact pure electricity, and diffused him by grounding him to a small puddle of water.

Needless to say, Zzzax was destined for a few more returns to the comics, and first did so in Hulk #183. Here, Bruce helped two scientists with a new project to record human brain waves. Unfortunately, this included the loose thoughts of Zzzax, who reformed in the lab and killed one of the scientists, who was blocking the creature from one of the lab assistants, whom he was in love with. Zzzax, in absorbing the scientist's brain waves, thought he was in love with the girl, and attempted to kidnap her. Bruce (now in pure HULK SMASH form) chased him to the rooftops and, with the help of another scientist, once again grounds Zzzax.

Zzzax made another brief appearance in The Incredible Hulk #285, where once again a power overload brings to life the electro-baddie. Bruce (now in the intelligent Hulk form) wills himself to change and fights off the creature, finally using the creature's weakness against him, connects himself to the power core and then grabs a hold of Zzzax to complete the circuit, and who is sucked back into the grid via the ubiquitous power reversal process.

Zzzax's final appearance in the Hulk series actually proved to be somewhat monumental. After being captured and sequestered in the secret Gammabase of the S.H.I.E.L.D. project, the creature was hooked up to the mind of Thunderbolt Ross, nemesis of The Incredible Hulk. Despite their efforts to synergize Ross and Zzzax, the evil electrode took over Ross' mind and escaped the base, hellbent on destroying Hulk once and for all. After a climactic fight with Rick Jones (in his Hulk mode) and Bruce, the new creature of Zzzax-Ross was finally defeated when Ross temporarily regained control of their fused body and flew off into oblivion.

Zzzax made one final appearance, in Cable issue #59 when a S.H.I.E.L.D. soldier wishing to draw Cable out into the open used a slight psionic trace of Zzzax to regenerate him with a large magnet. Big mistake. So, after Zzzax goes nuts and starts destroying people and things alike, Cable does finally appear, and using the old "water beats electricity" trick, subdues Zzzax for ... the last time?