Shedinja is a unique Pokémon introduced in the Generation III games. It evolves from Nincada when Nincada evolves into Ninjask while the player has an empty slot in their party and a Poké Ball in their bag. Shedinja is known for its ghostly appearance, resembling a hollow shell with a pair of wings. Shedinja has a distinctive ability called Wonder Guard, which allows it to be immune to all attacks except for those that are super effective against it. This makes Shedinja a strategic choice in battles, as it can withstand many hits, but it is also vulnerable to specific types like Fire and Dark.