As if The Chilling Adventures of Sabrina fans weren't already reeling enough from Netflix's cancellation of the series, showrunner Roberto Aguirre-Sacasa revealed the scrapped season 5 plan would have included a Riverdale crossover. The series began as a massive hit for the streaming service when it premiered in 2018, but as happens with many Netflix shows, the end of season 4 could indicate cast and crew contract negotiations were on the horizon.
Sabrina and Riverdale exist in the same universe, despite being on separate networks. A crossover between the two has been teased before, either in the form of behind the scenes pictures of the casts or as onscreen easter eggs. Riverdale's fourth season featured an appearance by Sabrina actor Ty Wood portraying Billy Marlin, a character first introduced on Sabrina as one of the players on the Baxter High Ravens football team. Meanwhile, Sabrina has featured multiple references to Riverdale, including the appearance of actor Moses Thiessen who Riverdale viewers know better as Ben Button.
The various mentions and references weren't just the writers having some fun with viewers, they were apparently building to a crossover called "Witch War," a concept Aguirre-Sacasa says the Sabrina writers were developing for season 5. "Thank you for all the love, #sabrinanetflix fans. Part Four is our best yet, and Part Five, “Witch War,” would’ve been AMAZING," the showrunner posted on Twitter, alongside some artwork from a planned comic book crossover event he promises is coming soon.
The previously mentioned crossovers featured on both shows were fun easter eggs. Still, the Sabrina writers took things a step further in season 3's third episode, "Chapter Twenty-Three: Heavy is the Crown," which followed Sabrina and Ambrose (Chance Perdomo) to Riverdale to find a crown hidden in the trunk of one of the Blossom family's maple trees. More than a mere mention or wink for fans, this crossover moment carried with it some big implications for the Blossom family's lineage, as it left many to wonder how a magical crown from Hell ended up hidden in a tree on the Blossom estate.
A few episodes prior, Prudence (Tati Gabrielle) has to disguise herself as an older woman in an attempt to lure the evil Faustus Blackwood (Richard Coyle) and inexplicably turns into actress Nathalie Boltt, who plays Penelope Blossom on Riverdale. At the time, this felt like one of several clever nods to viewers, but it turns out to be the seeds of a storyline that could have been explored in the "Witch War" crossover.
Sadly, Netflix viewers won't get to see the crossover since season 4 will be Sabrina's last. However, Riverdale is still airing on The CW, so perhaps some of the characters from Greendale could find their way over to their neighboring city on a more permanent basis. Not all hope is lost for the "Witch War" storyline, as the showrunner teased it will be continued in the pages of The Chilling Adventures of Sabrina comic book.
Source: Roberto Aguirre-Sacasa via Twitter