Gigantamax Pokémon are the big appeal of the new Pokémon Sword and Shield games. You encounter them in the Wild Area, where they pop in small glowing dens. They only come up every so often and are rare. However, some players have found a way to farm the Gigantamax dens so you can find the right one you want to catch.
The method is pretty simple. The first thing to do is to make sure you turn yourself to offline. When you do that, run-up to a den with a glowing red light to collect your Watts. After you receive your Watts, proceed to the Invite Others option and have it start loading.
While these options are loading, go to your home menu and go to your System Settings in your Nintendo Switch’s main options. Scroll down to System and go to Date and Time. You want to alter your time by a day and accept it. Go back to the main home menu and go back into your Pokémon Sword or Shield game.
Now, you want to quit out of the raid you’re processing. Clicking this should cancel your search and take you back to the main world where you should see the den in front of you start glowing again. Traditionally, if you’ve already collected the Watts from a den, you can no longer do so, but this time you can. You receive the Watts as if you never touched the den, and when you go to the raid, you should see a new Pokémon available that was different from your previous one.
You can continue to do this as many times as you’d like to collect the correct Pokémon you want to add to your roster. Some players have noted doing this method has corrupted their saves, so be careful when doing it.
PhillyThanzU discovered the method, and you can view him doing it from his Twitter account.
Fastest way to Hunt Gigantamax Pokemon in #PokemonSwordShield. Now you can finally get the Pokemon you want!
— PhillyThankzU? (@PhillyBeatzU) November 22, 2019