J. Jonah Jameson's son, John Jameson, was an astronaut selected for a secret mission to the moon. While collecting lunar rock samples, he came across a glittering red gemstone which, after his return to Earth, would later graft itself to his skin, causing him to transform into a wolf like humanoid creature known as Man-Wolf when exposed to the light of a full moon.
In Amazing Spider-Man #3, Spidey was badly beaten in his first-ever encounter with Doctor Octupus. Mentally defeated, Peter questioned his ability to go on as Spider-Man until he attended a school assembly where the Human Torch was giving a speech. The Torch encouraged the students to "never give up" even when things seemed tough. Peter took this message to heart, and in a rematch, defeated Doctor Octopus handily.
Mysterio (Quentin Beck) started his career as a Hollywood stuntman. He later branched into special effects but quickly grew tried of his constant backstage role, and when a friend jokingly suggested that, if he really wanted to become famous, he should take out one of the new costumed crime-fighters, Beck decided to kill Spider-Man, thus launching his criminal career.