A new mechanic has just been announced for the Pokémon series in Sword and Shield that allows Pokémon to change their form due to specific effects.
This was showcased with the new Pokémon Morpeko, the Two-Sided Pokémon and the Pikachu of the region, which has the ability to change its form depending on the use of certain items or their own ability.
When a Pokémon uses the Form-Changing ability, it doesn’t only change the Pokémon appearance but also changes the types of certain moves it knows or event grants in a brand new ability.
For example, Morpekos Hunger Switch ability is a new Ability that causes it to change its appearance each turn. Aura Wheel is Morpeko’s signature move, and it changes type depending on Morpeko’s form. In Full Belly Mode, the move is Electric type. In Hangry Mode, the move becomes Dark type.
This also causes its fur to change colors and triggers more aggressive and volatile behavior. The energy stored in its cheek sacs also changes from Electric-type to Dark-type.