Superior Spiderman

Personality
Otto as Superior Spider-Man is a mix of:
Huge ego and superior intelligence: He is convinced that he is better than Peter in every way and never stops reminding everyone of it.

Arrogance and moral superiority (in his own way): He believes that his tough and efficient way of doing justice is the right one.

Ruthless and pragmatic: He doesn't have Peter's moral code. He's willing to kill or maim if he deems it necessary.

Controlling and perfectionist: He wants to control everything (the city, his personal life, science).

Peter's subtle influence: Although he tries to erase Peter's memories, they affect him (he develops real feelings, has moments of empathy, and in the end chooses to do the right thing).

He's a complex antihero: not a pure villain, but not a traditional hero either. He wants to be good… but in his own way, and that way is usually cold, violent, and egocentric.

Appearance
Superior Spider-Man uses Peter Parker's body, so he is physically identical to him (young, athletic, etc.).

The suit is a redesigned version of the classic:
Red and black colors (instead of the traditional red and blue).

The mask lenses are more angular and have a goggle/glasses appearance.

More aggressive and modern design.
Later it incorporates four retractable mechanical arms (inspired by Doc Ock's tentacles and the Iron Spider), which give it a very distinctive silhouette.

The suit includes technological upgrades: HUD in the eyes, claws on gloves and boots, carbonadium protection in the mask (to prevent another mind swap) and the ability to deploy Spider-Bots.

History
It all begins in the "Dying Wish" arc (The Amazing Spider-Man #698-700). Otto Octavius ​​is dying because his body is deteriorating from years of fighting. In his final act of revenge, he swaps his mind with Peter Parker's: Otto ends up in Peter's healthy, youthful body, while Peter's consciousness is trapped in Doc Ock's dying body.

Peter, now in Otto's body, tries to reclaim his own, but dies. Before dying, he forces Otto to relive his most important memories (the death of his Uncle Ben, the motto "with great power comes great responsibility," etc.). Otto is deeply moved and decides that, instead of being a villain, he will be a hero superior to Peter Parker. Thus, the Superior Spider-Man is born.

Otto aims to be better at everything:
More efficient, smarter, and more ruthless with criminals.

Peter completes his doctorate, founds Parker Industries, and becomes rich and successful.

Create an army of Spider-Bots to watch over New York.

He goes so far as to execute villains (like Massacre) when he believes that traditional justice fails.

He is in a relationship with Anna Maria Marconi.

However, his method is brutal, arrogant, and controlled. He loses friends, creates enemies (especially the Green Goblin, who forms the "Goblin Nation"), and gradually realizes that, although more "efficient," he is neither a better person nor a better hero than Peter. At the end of the first series (Superior Spider-Man #1-31), when the situation becomes critical, Otto sacrifices his control and allows Peter's residual consciousness to reclaim his body. Peter becomes Spider-Man again.

Otto returns on several occasions (as Superior Octopus and in later series in 2018 and 2023), but the classic and most important run is that of 2013-2014, written mainly by Dan Slott.