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The Mayor of Castelia City (Japanese: ヒウンシティの市長 Mayor of Hiun City) is a character of the day who appeared in A Venipede Stampede!.
The mayor had given Trip and a few other Trainers permission to use Fire-type Pokémon against the swarm of Venipede that was plaguing his city. Ash and his friends did not like this, but the mayor informed them that they had to either contain the Venipede or evacuate the citizens. Burgh explained to him that this was the wrong way to deal with the problem, since there were too many people and it would only make them angrier. The mayor listened to Burgh's words and decided to let him handle the Central Plaza and find the leader. However, he warned that if he was unsuccessful, he would take matters into his own hands.
He later appeared to be overjoyed at the gang's work in rounding up all of the Venipede. Professor Juniper then showed him the massive flow of energy going on in the Desert Resort.