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May's Munchlax (Japanese: ハルカのゴンベ Haruka's Gonbe) was the fifth Pokémon caught by May during her travels through Hoenn, making her the first main character to catch a Generation IV Pokémon. His voice actress in Japanese is 佐藤智恵 Chie Satō, and his English voice actors are Darren Dunstan (4Kids dub) and Billy Beach (Pokémon USA/TAJ Productions dub).
May caught Munchlax in the episode Berry Berry Interesting. Munchlax was the only Pokémon May could find that liked her custom PokéBlocks, May's Purple Surprise, ironically named in Japanese as Haruka's Delicious, so she was determined to catch him. After being accused of eating a group of children's PokéBlocks and berries, he eventually did after the real perpetrators, Team Rocket, were caught. May threw a Poké Ball while he was distracted, but Munchlax noticed and ate the Poké Ball; seconds later, the Poké Ball activated from inside Munchlax, and he was caught. In Less is Morrison, May invented May's Pink Surprise (Haruka's Delicious 2), by altering a recipe she got from Professor Oak, which when fed to Munchlax renders he bloated and satiated. It was the only one of May's Pokémon that wasn't used in her first Grand Festival.
In Sweet Baby James, Munchlax was breathing irregularly and refusing food. May worried about Munchlax until they found James's vacation home, where an old couple allowed to take in Munchlax and James's Chimecho. It slept next to Chimecho as it healed. Jessie and Meowth stole Munchlax and Mime Jr., plus some other Pokémon. However, the bag split and Munchlax (who was by now fully healed) and all of the other Pokémon were released. Munchlax continued to follow May on the journey.
Munchlax also continued traveling with May when she left to compete in the contests in Johto.
Moves used
Trivia
According to Pokeani, Munchlax is the only male Pokémon May owns.
For more information on this Pokémon's species, see Munchlax.