The Ponpoko Morph Gun is a transformation ray gun created by Senbei Norimaki. By saying the name of an object in the microphone on the back that pistol, the user can turn anyone or anything in this object. For them to return to normal, the user must say "turn back!"
The Ponpoko Morph Gun is introduced in the chapter "The Ponpoko Morph Gun" and its anime counterpart "Transform Ponpoko Gun". Senbei tests it on Arale Norimaki, turning her into a television screen, and then on Gatchan, turning him into a pig. Arale then uses it to turn a cockroach into Senbei Norimaki, and Senbei Norimaki into a frog. As a revenge, Senbei turns Arale into a fly. The doctor then uses the Ponpoko Morph Gun to increase the size of his lunch. Arale has then the idea to make the doctor more good-looking and turns him into a monster similar to Godzilla, as she thinks that Godzilla is beautiful.
The Ponpoko Morph Gun reappears in "Zippity-Doo Doctor". Senbei uses it to turn a giant alien gorilla into an ant to save Midori Yamabuki. As Midori was in the monster's hand, both are turned into ants. Senbei Noriaki steps on one of the ants thinking it is the monster, while it is in fact Midori.