I'm Rainbow Billy, the biggest big Billy
While not officially announced by the developer or publisher, a handful of retailer listings point to a physical release for Rainbow Billy: The Curse of the Leviathan on Switch.
As of right now, retailers show the game hitting retail shelves on May 31st, 2022. That’s almost certainly a placeholder date, so hang tight for more official release information in the near future.
As for Rainbow Billy: The Curse of the Leviathan in general, the game has been on the Switch eShop since October. If this game passed you by, you can read a quick recap for it below.
Rainbow Billy: The Curse of the Leviathan is a wholesome, creature capture, 2.5D Adventure-Puzzle-Platformer with over 30 hours of gameplay! It is a family-friendly, openly accessible, RPG-infused adventure in which you must save whimsical creatures by bringing back color to the world you once knew!