Fans are still many months away from the second season of "Stranger Things." Fortunately, the creators have taken pity to the breakout show's aficionados and released a brief but thrilling teaser trailer earlier this week.

Not much has been revealed in the teaser, but it showed a new monster that seems to be scarier than the Demogorgon. The huge creature was silhouetted in the red sky by lightning, and it resembles a creature called Thessalhydra from the boys' Dungeons & Dragons game.

The board game played a vital role in Season 1. The Thessalhydra, however, is depicted as a multi-headed monster, whereas the creature shown in the teaser is spider-like and has eight legs but with only one head.

Something odd, meanwhile, is happening to Will (Noah Schnapp). In the final moments of Season 1, the child vomited a slimy slug and he appeared to have returned to -- or seen -- the Upside Down for a split second. This suggests that he might still be connected to the Upside Down despite escaping it.

According to Polygon, there's a possibility that Will became a portal between our world and the Upside Down when he got out of the latter. Being infected with the parasite probably turned Will into a bridge where the Upside Down's creatures can use to travel to our world. Netflix's promotion for the upcoming season, "The world is turning Upside Down," heavily hints of this theory.

Another theory posted on Reddit speculates that Will is becoming the Thessalhydra after the Upside Down infected him. The slug that crawled out of his mouth may signal the monster's early beginnings.

"Stranger Things" Season 2 will still focus on the characters already established in Season 1, meaning fans will see more of Eleven (Millie Bobby Brown), Mike (Finn Wolfhard), Dustin (Gaten Matarazzo) and Lucas (Caleb McLaughlin). The second season, however, will have a bigger and darker scope, though it will still showcase the "magical storytelling" established in Season 1, Vanity Fair reported.

New cast members will be introducing, including the 13-year-old "tough and confident" Max (Sadie Sink), her 17-year-old "violent and unpredictable" brother Billy (Dacre Montgomery), the "emotionally damaged" Roman (Linnea Berthelsen), Bob Newby (Sean Astin) as Joyce's (Winona Ryder) love interest and Dr. Owens (Paul Reiser) of the Department of Energy.

"Stranger Things" Season 2 will have nine episodes, with the last episode titled "The Lost Brother." Co-creator Matt Duffer said that the stakes are higher in Season 2 because it's the town that's going to be in danger, whereas in Season 1 it was just Will, according to Entertainment Weekly. The second season will be released on Netflix on Halloween.