I've been seeing this a lot and I'm confused about what that format is in Showdown!. Thanks!
Super Staff Bros is a ladder format featuring random teams made up of sets created by Pokémon Showdown! staff members. That alone wouldn't be very interesting, though; what makes Super Staff Bros special is that each Pokémon has a custom move, as well as other special touches such as the freedom to use any existing move or ability on any Pokémon, custom abilities, custom items, and extra effects called innate abilities. Not every Pokémon will have all of these to preserve balance, but all Pokémon will have a custom move. These custom moves can do some pretty crazy things that you would never see in a standard Pokémon match, such as a Stockpile ability powered by rain, a gacha system based on the colors of Minior, and even a move that changes the user's set mid-battle when used! As mentioned, each Pokémon in the format is created by a staff member. In addition to that, each Pokémon is named after the staff member that created it and will post messages on their behalf in chat when being switched in, switched out, or knocked out. Mega Evolutions and Z-Moves are also included in Super Staff Bros, and their limitations have been removed. This means each Pokémon may use one Z-Move per battle, and there is no limit to how many Mega Evolutions a side may use. Other than these changes, it's just a normal Pokémon battle; the first trainer to KO their opponent's team wins!
Source
So tldr, Super Staff Bros is a PS! format where the PS! Staff make their own custom sets and we the people can fight with 'em. It also has a ladder, so it's pretty popular.
The whole roster can be found here.
Hope it helped!
