>>110477695Finn's character didn't "develop". That would imply Finn's character made some definite shift in personality or attitude based on changing events. But Finn didn't change from one kind of person to a slightly different kind of person; rather, his personal qualities eroded. He became more diffuse, more changeable, less individualized.
This was a trend that affected pretty much all of the main characters. Marceline went through it, and eventually Princess Bubblegum and even Jake. Ice King was, I think, the only one that didn't because his character was simply too eccentric.
