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Benny (Japanese: テル Teru) is a character of the day from the episode Tricks of the Trade.
Benny is a Pokémon Trainer who lives in Palmpona. He wanted to trade his Wobbuffet for a stronger Pokémon. Ash and his friends tried to help Benny locate a Trainer willing to trade with him; he briefly contemplated asking if Ash would be interested in trading his Tauros, but decided not to after he overheard Ash saying that he wasn't there to trade. A Trainer with a Stantler decides to trade with Benny, but bails at the last minute when he decides he would rather have a Flying-type Pokémon.
Meanwhile, the Magikarp salesman, running away from James, bumped into Jessie and sent her flying. She bumped into the trading machine, and her Poké Ball containing her Lickitung fell into the machine. The trade went through, and Jessie, not realizing what happened, took Wobbuffet's Poké Ball and ran off.
By the end of the episode, Benny was showing off his new Lickitung to Ash and his friends. He called into the distance, promising to Jessie that he would take care of Lickitung and hoping that she would take care of Wobbuffet. He presumably still has Lickitung, but neither he nor Lickitung have been seen since then.