Where are the three Max mushrooms?
Max Mushrooms are very important in the Isle of Armor DLC, as they can be used to create Max Soup which gives your Gigantamax Pokémon powers. As part of the second Dojo Master Mustard trial, you have to find three of them in the wild.
As soon as you leave the Dojo, Master Mustard will take you to the Forest of Focus where he says the Mushrooms should be. However, he then realizes that they may be missing and points you in another direction you will need to take to really find them.
After regaining control, you want to head to the Forest of Concentration, but we need to head to a special cave here instead of looking for where everyone is. This cave is known as the Warm-Up Tunnel, but it's going to take a bit of maneuvering to get there. Head over the nearby bridge first and start going down the path to the right until you see a river. Follow the path along the river until you meet another bridge, but this time you want to go left instead. Take the next left to cross another bridge and you'll find yourself in a new area known as Training Lowlands. From there you should see a tunnel in the distance, so head towards it.
As soon as you are in the warm-up tunnel, go ahead and take the right path. You should notice some large pink mushrooms right in the path that you can interact with, so just do that. This will inspire Klara to show up and challenge you for the Max Mushrooms, so take her like you've done in the past. Once the battle is over, the three Max Mushrooms are in your hands and all you have to do is return to the Dojo to return them.