It’s a very bittersweet time for cartoon fans, as animation legend Butch Hartman announced yesterday via his YouTube channel that he would be leaving Nickelodeon. It’s not clear what exactly led Hartman to come to this decision after working at Nickelodeon for 20 years, but he assures fans that he is parting with Nickelodeon on good terms. For the most part, it seems Hartman left to pursue new projects with different companies and to produce content himself. You can watch Hartman’s video “Why I Left Nickelodeon” for yourself below.

Hartman’s legacy at Nickelodeon

Originally working for Hanna-Barbera, Butch Hartman first started out at Nickelodeon by participating in the “Oh Yeah! Cartoons” animation showcase with his pilot “The Fairly Odd Parents.” The pilot proved so successful it was picked up by Nickelodeon for a six-episode run. “Invader Zim,” another show picked up by Nickelodeon would air the same night as the “The Fairly Odd Parents” on March 30, 2001. Unfortunately, while “Invader Zim” didn’t last very long, “The Fairly Odd Parents” would run for ten seasons, with season ten ending in 2017. However, “The Fairly Odd Parents” wouldn’t be Hartman’s only show though. In 2004, Hartman’s second show “Danny Phantom” aired.

“Danny Phantom” was a show about a young boy named Danny Fenton who received ghost powers after stepping into a very strange machine.

After gaining these powers, Danny would go on to become a ghost fighting superhero who would have to balance out ghost hunting along with his family and school life. “Danny Phantom” would run for three seasons before coming to an end.

About three years after that, Hartman would come out with another animated series called “T.U.F.F. Puppy,” that followed the adventures of a secret agent dog. “T.U.F.F. Puppy” would also go on for three seasons before ending as well. Three shows weren’t it, as Hartman’s final show on Nickelodeon “Bunsen Is a Beast” would begin airing in 2017, before ending its first season in February of this year.

What’s next for Hartman and the fates of his remaining shows

While Hartman is off pursuing several new projects, it seems likely that both “Bunsen is a Beast” and “The Fairly Odd Parents” are finished. Hartman himself all but confirmed “Bunsen is a Beast” would end with its first season, but nowhere in the video does his discuss the fate of “The Fairly Odd Parents.” Despite Hartman leaving, it is possible “The Fairly Odd Parents” could continue without him. Even if the show would never be the same without him, many animated shows have continued without their creators including Cartoon Network’s “Adventure Time” and “Clarence” as well as Nickelodeon’s “SpongeBob SquarePants” and “The Loud House.” However, considering “The Fairly Odd Parents” moved to Nicktoons last year, combined with that fact it’s been a full year since any new episodes have aired, it seems like now would be a good time as any for the show to end.

In the less sad news, Hartman has confirmed to have several different projects already in the works, including a project called “Elf Detective.” While we didn’t get much on what “Elf Detective” is, Hartman did show interest in potentially releasing the show on his YouTube channel instead of selling it to another network. He also confirmed that he was working with to create something, but couldn’t say more than that as he is under contract. According to Variety, “Under his non-exclusive, three-year deal with, Hartman also is being named senior creative consultant. In that role, he’ll provide creative input for the startup’s digital channels, creator partnerships, and premium content.” Either way, it looks like Hartman has plenty to keep him busy and that he has no plans on slowing down anytime soon.

Here’s to hoping Butch Hartman’s new adventure brings him continued success and happiness. Despite this setback, Nickelodeon will continue creating new content of its own including a new 2-D animated “Ninja Turtles” show as well as an “Invader Zim” TV movie.