The cast of "Teen Wolf" Season 6 returned to San Diego Comic-Con for the last time and the mood in Hall H was undoubtedly nostalgic. Although Dylan O'Brien was not listed as one of the cast members who would attend the panel, the "Maze Runner: The Death Cure" star showed up to reunite with Tyler Posey and the "Teen Wolf" family.

Needless to say, both O'Brien and Posey got emotional when discussing their six-year history with the MTV series. The "American Assassin" actor even admitted that he was always eager to go back and work on "Teen Wolf" because he considered the show his "home."

The 'Teen Wolf' SDCC panel surprise guest

Dylan O'Brien has been a part of the "Teen Wolf" panel at SDCC for several years.

However, fans began to worry when it was reported that the "Maze Runner 3" actor was not listed as one of the attending cast members. Luckily, O'Brien showed up at Hall H on Thursday to help introduce the final season's new trailer via Twitter.

O'Brien's appearance and the debut of the new teaser were not the only surprises during the show's SDCC panel. The presentation opened with a video message from Tyler Hoechlin and Ian Bohen as they introduced an exclusive clip featuring Derek Hale. The scene reportedly confirms that long-time villain Gerald Argent is ready to hunt again and this time, he is planning to catch Derek.

The clip from "Teen Wolf" Season 6B immediately had SDCC attendees wondering about Gerald's evil scheme. However, the highlight of the panel was the awesome reunion between the actors who play best friends Stiles and Scott.

The brotherly bond

Tyler Posey revealed that he and Dylan O'Brien sparked an instant friendship when they first met in the first season of the MTV show.

"I never had too many buddies growing up as an actor that were in the industry," the actor stated, as per Entertainment Weekly. "It wasn’t just work, it was friendship and finding my purpose in life and becoming an adult and making a difference."

O'Brien shared that their friendship made him feel like being on the show "was never a job." The "American Assassin" star even stated that he tried to squeeze "Teen Wolf" into his busy schedule while juggling other projects because "I just couldn’t wait to come home."

The final season of "Teen Wolf" will pit Scott and his pack against a terrifying new villain that threatens to destroy everyone in Beacon Hills. Find out if the young Alpha and his friends will manage to save their home when the last 10 episodes premiere on MTV on July 30.