MultiVersus already has its share of the DC Comics characters and it appears as though Player First Games isn’t done with that universe. New datamined voice lines from the game have audio of Mark Hamill’s Joker acting as the announcer.
— Laisul – MultiVersus Leaks and News (@LaisulMV) September 27, 2022
As noted by MultiVersus dataminer LaisulMV, these lines have Joker saying “Ooh, we’re out of time,” “Only 30 seconds to mayhem,” and other quotes that talk more broadly about the match. None in the clip pointed to him being in the game as a playable fighter, but it’s possible he might join the roster down the line as LaisulMV also noted of some “ability” voice lines. However, those didn’t come with audio, meaning it’s a bit harder to pinpoint whether or not he’ll be playable.
Joker was included in one of the game’s more substantial roster leaks, though. That leak included a few characters like Rick, Morty, LeBron James, and Gizmo, all of whom have joined the roster since, which gives the other parts of the leak more credibility.
Hamill is known for his portrayal of Joker in various forms. He started playing the character in Batman: The Animated Series in 1992, a role he continued in other animated shows and films. Hamill has played the twisted clown in other video games, too, mostly notably Rocksteady’s three Batman: Arkham games.
LaisulMV, under a different and now-suspended account, also previously found audio files pointing to a Beetlejuice, The Wicked Witch from The Wizard of Oz, and Adventure Time‘s BMO and Lady Rainicorn. None are currently in the game as of yet, but are likely in the pipeline.