The official Pokémon website has announced that Pokémon Sword and Pokémon Shield Max Raid Battles through July 19th, 2020, at 4:59 p.m. PDT, plyaers will be more likely to find Kingler, Mantine, Sharpedo, Wailord, Jellicent, and Pyukumuku and they may even encounter a Shiny Wailord!

Aquatic Pokémon, Including Shiny Wailord, Arrive in Max Raid Battles

Pokémon Dens are getting a splash this summer in Pokémon Sword and Pokémon Shield.

Summertime may bring the heat, but Pokémon Sword and Pokémon Shield Max Raid Battles are staying cool thanks to the sudden appearance of seafaring Pokémon. Through July 19, 2020, at 4:59 p.m. PDT, you'll be more likely to find Kingler, Mantine, Sharpedo, Wailord, Jellicent, and Pyukumuku appearing in Max Raid Battles. And if you're lucky, you may even encounter a Shiny Wailord!

To challenge these Pokémon in a Max Raid Battle, you'll need to connect your Nintendo Switch system to the internet. Then, whenever you see a pillar of light shining from a Pokémon Den in the Wild Area, you can walk up to the Pokémon Den and interact with it to start a Max Raid Battle with a Dynamax Pokémon.

Source: https://www.pokemon.com/us/pokemon-news/aquatic-pokemon-including-shiny-wailord-arrive-in-max-raid-battles/