Gigantamax Rillaboom is a special form of the Pokémon Rillaboom that can only be achieved through Gigantamaxing. When Rillaboom Gigantamaxes, it grows in size and gains a unique appearance, with its drum-like hands growing larger and its body taking on a more imposing form. In addition to its increased size and altered appearance, Gigantamax Rillaboom also gains access to a powerful G-Max Move called G-Max Drum Solo, which can deal massive damage to its opponents. **

In Pokémon Shining Pearl, Gigantamax is a special phenomenon that allows certain Pokémon to take on a new, more powerful form during battles. When a Pokémon Gigantamaxes, it becomes larger and gains a unique appearance, as well as access to a special G-Max Move that can deal massive damage to opponents. Only specific species of Pokémon are capable of Gigantamaxing, and they must have the Gigantamax Factor in order to do so. Players can encounter and battle Gigantamax Pokémon in Max Raid Battles and use the power of Gigantamax in their own battles to gain an advantage. **

Gigantamax doesn't work in Pokémon Sword and Shield because the game developers have not included the feature in those specific games. Gigantamax was introduced in the subsequent games, Pokémon Sword and Shield, as a new mechanic that allows certain Pokémon to transform and gain access to exclusive G-Max moves. Therefore, players can only experience Gigantamax in the games that have been designed to include this feature. **

To achieve the Gigantamax form of Urshifu, you will need to have the Isle of Armor expansion for Pokémon Sword and Shield. Once you have the expansion, you will need to train Urshifu in one of the two towers on the Isle of Armor: the Tower of Darkness for Single Strike Style or the Tower of Waters for Rapid Strike Style. By completing the challenges in the tower and defeating Urshifu in a final battle, you will unlock its Gigantamax form. **

To achieve the Gigantamax form of Wulaosu, you will need to have a Wulaosu that is capable of Gigantamaxing. This can be obtained through Max Raid Battles or by receiving one as a gift in special events. Once you have a Gigantamax-capable Wulaosu, you can activate its Gigantamax form during battles by selecting the Dynamax option and then choosing the Gigantamax option. This will allow Wulaosu to transform into its Gigantamax form and gain access to its unique Gigantamax moves. **

To achieve the Gigantamax form of Urshifu, you will need to have the Isle of Armor expansion for Pokémon Sword and Shield. Once you have the expansion, you will need to train Urshifu in one of the Towers of Two Fists on the Isle of Armor. By defeating the Tower and completing the training, Urshifu will be able to Gigantamax during battles. **

In Pokémon Shield, you can gigantamax your starter by obtaining a special item called the Max Soup. To get the Max Soup, you need to progress through the Isle of Armor expansion and complete the main storyline. Once you have the Max Soup, you can use it to gigantamax your starter Pokémon by giving it to a specific character on the Isle of Armor. After consuming the Max Soup, your starter Pokémon will gain the ability to gigantamax during battles. **

No, the Gigantamax Charizard has not simply disappeared from Pokémon Sword and Shield. It is still available in the game through various methods such as Max Raid Battles, special events, and trading with other players. Players can also obtain Gigantamax Charmander and evolve it into Gigantamax Charizard. While it may not be as common as other Pokémon, it is still possible to obtain and use Gigantamax Charizard in the game. **