Harry Osborn first appeared in The Amazing Spider-Man #31 (December 1965),[4] and was created by writer Stan Lee and artist Steve Ditko.

[7] Several years later, the Spider-Man writers made plans to reveal that the mysterious villain Gaunt was Harry Osborn, who was still alive and had orchestrated the entire "Clone Saga", but an editorial edict prevented this from coming to fruition.

Spider-Man uses this to his advantage during one battle with Green Goblin; he is able to stop the fight by showing Norman his son's emaciated condition, brought on by an accidental drug overdose.

One day, to his shock, he finds a Spider-Man costume in Peter Parker's apartment and realizes that his best friend is the man he blames for his father's death.

[volume & issue needed] For a while, Harry's life seems back on track; his company begins turning profits once more, and he develops a romance with Liz Allan after they meet at the wedding of Betty Brant and Ned Leeds.

Harry has now convinced himself that Peter Parker resents the Osborns' "stable family life" due to never having been wanted by his own parents or guardians, when in fact it was the complete opposite.

[20] Harry investigates his father's old hideouts and notes, and finally uncovers and ingests the formula for the original Green Goblin's superhuman strength.

This computer facsimile of Harry and its robotic drones (which resemble female versions of Green Goblin) were all destroyed by Spider-Man and the Molten Man who manage to save Normie from it.

Sometime before his final confrontation with Spider-Man, Harry had employed the Chameleon to construct Life Model Decoys of Peter's parents to play with his emotions.

Peter goes temporarily insane from the shock, even briefly rejecting his identity until the return of his clone Ben Reilly snaps him back to reality.

This Harry, possessing all the memories of the original, refuses to entertain the idea of his son becoming a killer, and assists Spider-Man in defeating the leader of the group.

Strange, Mister Fantastic, and Iron Man to help him wipe out all evidence and memory of Spider-Man's secret identity (save from Mary Jane), Harry recalls his actions as the second Green Goblin but no longer remembers that Peter Parker is the web-slinger.

Harry later states that he wants to talk to Peter, who moments earlier was kissed by Lily, and is seen leaving with a mysterious canister labelled "Prometheus X-90".

[volume & issue needed] Prometheus X-90, it is revealed later, was developed as a successful cure for Mark Raxton's condition as Molten Man.

[35] In the midst of a battle between Menace and Spider-Man, Harry confronts and shoots her with that chemical, which is a type of antidote that reverts her back to her human form.

Fearing the damage that could be done with the American Son armor and perplexed by his encounter with Gabriel, Harry decides to figure things out on his own.

Meanwhile, Gabriel confronts the American Son armor and is revealed to have developed a split personality similar to Norman's after his exposure to the Goblin Formula.

[53] As part of the All-New, All-Different Marvel branding, Harry Osborn and his young son Stanley finally came out of hiding, following his father's, the Goblin King, defeat.

[56] It is revealed over the course of Nick Spencer's run as writer on The Amazing Spider-Man that, upon dying, Harry's soul was transported to Hell, where he encountered the demon Mephisto, who labels him as the Goblin Prince.

In the new universe created by the folding of reality in Infinity Wars, Harry's father Norman is fused with Jack Russel and becomes Goblin by Night.

After several emotionally charged encounters with Spider-Girl, Normie eventually reclaims his sanity and the blood feud between the Parkers and the Osborns is finally brought to an end.

Having secretly survived his final battle with Spider-Man, and still unhinged due to the side-effects of the Goblin formula, Harry carries out a vengeful campaign against the Spider-Men with the aid of Kaine.

[76] After Norman eventually subjects himself to the OZ Formula, the Green Goblin kills Martha and attempts to kill Harry, because of which he initially goes missing but eventually shows up outside Midtown High following Spider-Man's battle with Green Goblin there which nearly destroyed the school and tells MJ, Flash Thompson and Kenny Kong that the monster is his dad.

In this reality, Harry is the heir of Oscorp, one of the largest companies of the North American Union, a regional power bloc which includes the former United States territories.

Weeks after that, Harry and Gwen Stacy, his wife, are told that the inheritance of the Osborn estate is now owned by them, while it might take awhile before he can consolidate control over the company.

Harry then is called for a meeting with Wilson Fisk, the newly appointed Shadow Governor of New York, who asks him to help take care of Stark/Stane's due the power vacuum caused by the fall of the Starks.

Two weeks later, Harry, Gwen Stacy, and their employee Otto Octavius raid a hidden repository of Howard Stark, containing his armors, archives and suit designs.

Fisk then goes on the attack where it's shown his body was augmented enough to make the fight difficult and causing Green Goblin and Spider-Man to do a tactical retreat.

Octavius considers them as being built with different types of engineering, listing the Green Goblin armor as an advanced piece of hardware while the internal capabilities of Peter's suit are harder to pinpoint.

[88] Green Goblin and Spider-Man learn from Iron Lad that the picotech was revolutionary and that Maker had a secret file where anyone that was deemed "mission" critical had to go.