The latest Max Raid Battle event in Pokémon Sword and Pokémon Shield is just too exciting to clam up about. Until May 22, 2022, at 4:59 p.m. PDT, Shellder will appear more frequently in Pokémon Dens. Lucky Trainers might even encounter a Shiny Shellder!
For an opportunity to encounter this Pokémon in a Max Raid Battle, you'll need to connect your Nintendo Switch system to the internet through Y-Comm or by selecting Mystery Gift in the X menu, then selecting Get the Wild Area News. After that, whenever you see a pillar of light shining from a Pokémon Den, you can walk up to the Pokémon Den and interact with it to start a Max Raid Battle with a Dynamax Pokémon. This event does not affect the Pokémon encountered within Dynamax Adventures.
Be sure to read our Pokémon Sword and Pokémon Shield Max Raid Battle Tips article for advice on how to topple this opponent. Don't wait, though—you don't want to miss out on the chance to add this Pokémon to your team!