The Incredible Hulk #109

In "The Monster and the Man-Beast!", the Hulk crashes into the Savage Land after stopping a missile launch, transforming back into Bruce Banner. Rescued by Ka-Zar, Banner is drawn into a desperate mission to stop a mysterious machine throwing the planet’s weather into chaos—but when the Swamp Men attack, he reverts to the Hulk, forgetting the true threat entirely. Written by Stan Lee and illustrated by Frank Giacoia and Herb Trimpe, with inks by John Severin and letters by Artie Simek, this 1968 classic features a cover by Herb Trimpe and John Severin that captures the jungle’s wild energy.