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Misty's Togetic (Japanese: カスミのトゲチック Kasumi's Togechick) was found as a Pokémon Egg by Ash Ketchum in Grandpa Canyon in EP046. Ash, Misty, Brock and Meowth fought over the egg and competed to determine who would be the eventual owner. When the Pokémon Egg hatched into Togepi, the first thing it saw was Misty, and it chose her as it's trainer, thinking that she was its mother. It ended up being the sixth Pokémon Misty got in the Kanto region.
Although Togepi appeared harmless, it sometimes used Metronome to get out of dangerous situations. The first time it happened was in Pikachu Re-Volts. Butch and Cassidy's Drowzee was using Metronome to attack Ash and his friends. Misty's Togepi began using it, causing an explosion that sent Butch and Cassidy flying. It happened again in In the Pink. A Rhyhorn was about to charge the group when Togepi used Metronome to use Teleport. It also used the move later in the episode to stop a Hyper Beam attack by a Nidoking by using Reflect.
Despite the fact that Misty knew Togepi could battle, she only used it one time to battle Ash. In The Totodile Duel, Ash was using his Pikachu to battle Misty for ownership of a Totodile. Misty used Togepi, because she knew Pikachu would never attack it. Using Charm, she ended up defeating Pikachu.
It evolved into a Togetic to defend the Togepi Paradise in A Togepi Mirage!, and left Misty to protect the Mirage Kingdom and the Togepi who lived there..