When he spoke about a sequel back in 2013, director Rich Moore said he wanted to try and work in mobile/casual gaming, and he also liked the idea of bringing in different Wreck-It Ralphs from mobile versions or Super Smash Bros.-like iterations of the character. He also stated that the cast and crew are open to the sequel, and plans to include Mario and Tron.Henry Jackman later said in 2014 that the sequel's story is being written.
On July 12, 2015, John C. Reilly confirmed the sequel and announced that he is signed on to reprise his role as Ralph.
On March 24, 2016, Rich Moore stated that a sequel is still being planned. Moore also hopes to specifically include an appearance from Mario, citing a "good relationship with Nintendo".
In an interview with Collider, Moore confirms that the film had been in development for about two and a half years by the time of its announcement. Development halted when Moore put focus on co-directing Zootopia, though things were set back in motion immediately after production on the film wrapped. Phil Johnston, a writer on the original film, was brought on to co-direct alongside Moore in response to his heavy influence on the first movie.
When asked about returning characters for the film, Rich Moore mentions that most of the previous vocal talents are being eyed for potential reprises. He also notes that Wreck-It Ralph antagonist King Candy (who died in the previous film) will likely remain deceased in the second installment.
However, Moore did hint a return for King Candy's voice actor, Alan Tudyk, in keeping with the tradition of having the actor voice a role in every Walt Disney Animation Studios film since Wreck-It Ralph.