It seems like Joker’s inclusion in Super Smash Bros. Ultimate has not been without its share of hiccups.
Some fans playing the new update have reported a softlock issue due to the DLC character’s flashy Final Smash move. Namely, using it during the single-player Classic Mode may leave players stuck on the final splash screen of Joker’s All-Out Attack.
Just did testing in spirit board, it doesn’t softlock there. Seems to just be classic mode
— duck (@TKOWL) April 18, 2019
As shown above, it looks like the issue is limited to Classic Mode for now – and should not affect the Spirit Board. We’ll report back if Nintendo deems the issue serious enough to address with a future patch.