DP193: Pewter Gym - The Greatest Crisis Ever!

Nibi Gym - The Greatest Crisis Ever! is a Diamond and Pearl that aired on February 3, 2011.

Plot
In Pewter City, Brock's little brother Forrest is working hard at attempting to take Brock's place as the city's official Gym Leader. During a match, Brock realizes that a Nurse Joy has been watching the entire time, introducing herself as a Pokémon League representative. Joy challenges Brock to a match, using his Sudowoodo against her Chansey, losing to Joy. With Joy unimpressed and thinking that Pewter Gym should be shut down, Forrest steps in just as Flint and Lola return from vacation. That night, Brock goes to Joy and tells her that his brother will be taking his place as a Gym Leader, and she agrees to take the challenge to see if he is worthy. In the battle, Forrest sends out his Rhyperior, but Joy sends out a Latias to challenge him with, but Rhyperior is still defeated. Even though Forrest has lost, Joy decides that he can now be the Pewter City Gym Leader, allowing Brock to pursue his dreams to become a Pokémon Doctor.

Debuts

 * Latias