Both movies feature their original voice casts, while their respective creators took up writing and directing duties. The films have been in the works for quite some time. Nickelodeon released a teaser for Static Cling in 2017, and said the spinoff of classic ’90s series Rocko’s Modern Life would be released in 2018, though that evidently never came to pass. Meanwhile, a teaser for Invader Zim: Enter the Florpus emerged at San Diego Comic Con last year.