Ep 20. The Little Big Horn

Ash, Misty and Brock arrive in a small town where they notice a bunch of Tauros running through the streets. Upon further investigation they discover that the Tauros are owned by a tough cowboy named Jackson who challenges Ash to a battle. Despite losing, Jackson invites the group to his ranch to help him with a problem he's been having. While wrangling a large herd of Tauros, one particularly large and aggressive Tauros keeps causing chaos and escaping the pen. Jackson warns the group to stay away from it, but Ash can't resist trying to catch it.

Meanwhile, Team Rocket has also stumbled upon the town and is plotting to steal all of Jackson's Tauros for themselves. They concoct a plan to capture the troublesome Tauros and use it to take down the rest of the herd.

As Ash and his friends chase after the wild Tauros, they come across a mysterious girl named Casey who claims to be a Pokemon trainer. She insists on helping Ash catch the Tauros and prove her strength as a trainer. Together, they come up with a plan to outsmart the Tauros and catch it, but not before the rest of the herd escapes.

With Team Rocket closing in, it's up to Ash and his friends, along with Casey and Jackson's Tauros, to take down the villainous trio and save the day. In the end, Jackson is grateful for the group's help and offers to train Ash's Pikachu in some new battling techniques before they continue on their journey.