Here’s some real leaks for Sword and Shield:

At the end of the game, all of the gyms rise out of the ground and come together to form one giant monkey-shaped machine. It’s called Gympanzee and it’s piloted by Tierno, the leader of the evil Team Spaghetti. He’s returned for revenge against Galar for their misdeeds. He uses the Gympanzee to flatten the ground and all ecosystems of Galar are destroyed. Everyone dies and Tierno returns to Kalos as a hero.