If the player uses the Mew glitch with a Special stat of 245, they will encounter a Channeler who has a ゥ. Its sprite freezes the game when sent out, both by the opponent and the player, making it impossible to battle with. This makes it one of very few glitch Pokémon whose back sprite also causes the game to freeze.
This glitch Pokémon article is part of Project GlitchDex, a Bulbapedia project that aims to write comprehensive articles on glitches in the Pokémon games.