Well, there are fanfictions where Spiderman gets his powers not from a single spider bite. Instead, he could be exposed to a series of bio - engineered substances that are spider - related. These substances interact with his DNA over time, gradually endowing him with the spider - like abilities we know, such as super strength, agility, and the ability to cling to walls.
Kraven's powers come from a mix of factors. He experiments on himself with special serums and constantly challenges himself in the wilderness to develop superhuman abilities like superior reflexes and acute perception.
Deadpool got his powers through a messed-up experiment. His body was subjected to a procedure that gave him superhuman abilities, but also left him scarred and crazy.
Spiderman gets his powers after being bitten by a radioactive spider. This bite gives him enhanced strength, agility, the ability to climb walls, and a 'spider-sense'.
The Hulk got his powers through a gamma radiation accident. Bruce Banner was exposed to a huge dose of gamma rays, and that's what transformed him into the Hulk when he gets angry.
Miles gets his powers through a spider bite, just like Peter Parker. But the circumstances and specific effects of the bite might differ in some details.
Morbius gained his powers through a failed experiment aimed at curing his rare blood disease. The process transformed him into a vampire-like being with enhanced strength and other abilities.
Deadpool got his powers through a rogue experiment. A weapon program tried to give him enhanced abilities, but it went awry, resulting in his unique powers and messed-up appearance.