Pokémon : S3 | E9 – The Little Big Horn

Upon arriving at a city, Ash and his friends see something poking out of a bush and identify it as a baby Stantler. Ash looks it up on his Pokédex while Brock attempts to lure it out by mimicking classic Stantler behaviors, and then by offering it food. However, Stantler remains hesitant and produces a nice scent from its antlers. A herd of Stantler suddenly charges at the trio, forcing them to flee. Once they are gone, the baby Stantler retreats into the bushes. The trio starts searching for the Stantler after Brock noticed its leg was injured. Officer Jenny approaches them and takes them back to her office to file a report. She informs them that the Stantler herd has been terrorizing the town. However, Brock is skeptical and suggests there must be more to them than meets the eye.

Just then, they find Team Rocket being chased. After performing their motto, they explain they were attempting to capture all of the city park's Stantler, but were forced to abandon their plan after being chased by a herd of them. Suddenly, a sweet smell wafts over everyone, and a herd of Stantler runs into town. Team Rocket flees, while Jenny ushers Ash and Misty into the police station for safety. Brock remains outside and witnesses the Stantler seemingly running through light poles and walls. Ash urges Brock to run, but Brock waits for the herd to hit him. However, the herd of Stantler goes right through him, and Ash and Misty are amazed as the illusions begin to fade.
(Source: Bulbapedia)