Oishi: Demon Hunter (partially found web series sequel; 2018)
Oishi: Demon Hunter was a planned sequel series to the Smosh SHUT UP! Cartoons series Oishi: High School Battle. Starting production around 2017, it was planned to continue the series, with Oishi's original voice actor Cathy Shim, returning to the role once again. The whole series seemed to be filmed and was nearing completion, until on July 31st, 2018, when go90, the video service and app which planned to air the series, shut down. The series seemed to be cancelled and thus, has never been released. It's unknown how much was exactly completed.
go90 and Production
After Oishi's final episode was released, it was unknown if the series would continue on, especially since Shut Up! Cartoons stopped uploading not too long after the series ended. However, the company who owned Oishi, DEFY Media, teamed up with Verizon to make a sequel series on the go90 streaming service. The series seemed to be fully filmed and animation had gotten pretty far along. However, due to go90's closure, the series was never released and it's unknown if the series was fully completed or not.
An unfortunate effect this had was that Oishi was completely removed from Smosh's website and the SHUT UP! Cartoons channel as it was planned to migrate over to go90 once Oishi: Demon Hunter was completed. Since it never did, there is no official way to watch the episodes, although reuploads of every episode exist.
Not much is known about the series, other than an IMDB page which lists the cast and that there was going to be 20 episodes of it. A few clips and test animations have resurfaced, however, a full episode has yet to resurface and it's unknown if the series will ever be released in full.