Super Smash Bros Ultimate has a fighter pass that will add five new characters to the game. Three of these have been revealed by now while the fourth one just leaked.
Super Smash Bros Ultimate fighter pass will add Joker from Persona 5, Hero from the Dragon Quest series, Banjo & Kazooie, and two more characters that are not confirmed yet. Nintendo UK has accidentally leaked the fourth fighter that will be a part of the challenger pack. This was seen in a listing for Challenger Pack 4.
The listing confirmed that the following new content will be added to the game with this pack.
This has been the standard so far for every challenger pack, which is a part of the fighter pass for Super Smash Bros Ultimate. What was not confirmed was the origins for this character but a copyright notice mentioning SNK has basically hinted that this might be from one of the many SNK fighting games. This could mean anything from Samura Showdown to The King of Fighters.
There are rumors of a brand new Nintendo Direct that will happen in th first week of September. It is possible that Nintendo will reveal the details on the next challenger pack for the game during this time. The listing for challenger pack 4 also went up ahead of the rumored Direct so there is a good chance this might be true.
Nintendo is planning to get all of the DLC for the game out before the end of February 2020. Banjo & Kazooie is next to launch in the game and that will be likely followed by this challenger pack 4.