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Team Rocket's map of Lake Rage, used during the project
Project R, short for Project Revolution, is a Team Rocket operation to artificially evolve their Pokémon with evolution-inducing waves. The operation is based around the Lake of Rage in Johto.
In the anime
Appearing in Talkin' 'Bout an Evolution and Rage Of Innocence, Project R uses Team Rocket technology to produce evolution-inducing waves from a Team Rocket research facility at Lake Rage. Team Rocket Grunts assist in the project, as do Professor Sebastian and Tyson.
The operation was intended to make Team Rocket's Pokémon evolve to be stronger, creating the ultimate Pokémon army. However, aside from evolving a Magikarp into the Red Gyarados, it was unsuccessful, and only caused the Pokémon in the area to become lethargic and appear sick.
Professor Sebastian learned that the evolution-inducing wave can also be used as a great weapon, noting how weakened the group's Pokémon were in the wave's vicinity.