The "X-Men" universe is expanding to include other Marvel favorites, "Gambit" and "Deadpool."

According to executive producer Simon Kinberg, the "X-Men: Days of Future Past" reboot allowed the team to create a new world where the different comic book characters can co-exist.

"The idea is that we've sort of reset the timeline after 'Days of Future Past' in some ways, and if not erased, certainly allowed for change from 'X1,' '2,' '3,' everything from 'Days of Future Past' forward, 1973, everything we set now becomes canon," he explained in an interview with MTV. "So the 'Gambit' movie, the 'Deadpool' movie, will exist in a world that acknowledges whatever happened in 'Days of Future Past' and moving forward."

"Doesn't mean they'll always interact with those characters, obviously, it's not like every movie has all the characters, but they all have to exist within the same rules," Kinberg clarified. "There will be interplay between different characters in different movies."

There aren't concrete plans to stage a massive crossover film, but even iconic characters of different franchises showing up in each other's films is cause for excitement already.

After all, Gambit already made his debut in "X-Men Origins: Wolverine," so it might be possible to see Channing Tatum's character appear again in future "X-Men" adaptations. X-Men superhero Colossus is already confirmed to be part of "Deadpool," although he will be played by Andre Tricoteux instead of Daniel Cudmore, according to Cinema Blend.

These recent moves suggest that a more fluid universe is being designed for the three films, with potential for endless development.

Even long-time fans may find it tricky to keep track of the plot details and characters, but Kinberg assured that he has the whole project locked down.

"I don't have it up on a wall, but I have it on my computer, and I have it sort of tattooed on my brain now too," Kinberg told MTV. "Nothing external, so that if I get knocked over the head, no one can read it. It's literally behind my eyelids."

He concluded, "But yeah, we have a clear sense of the directions we want to take them in and in my mind at least, how we could start to cross-pollinate sort of with those characters that have their standalone movies."

Next year is set to be an important year for the trio of films with "Deadpool" slated to hit theaters on Feb. 12, "X-Men: Apocalypse" on May 27 and "Gambit" on Oct. 7.