From the Super Mario Wiki
Retrieved from "https://www.mariowiki.com/index.php?title=Napse&oldid=2757736"
A Napse is a neuron-like enemy inside Bowser's body in Mario & Luigi: Bowser's Inside Story and Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey. They are located in the Energy Hold, and look like round red cells ringed by moving dendrites. Their name comes from "synapse", which is the junction between nerve cells.
A Napse will attack Mario or Luigi using electrical discharges that are colored either red, or green. One of its attacks includes summoning two energy balls colored red and green. It will then spin around turning both the red and green balls into blue ones. The energy balls will then hit the respective brother, depending on its former color, so the player needs to keep an eye on the order the Napse has the energy balls. This attack is avoided by jumping. Another one of its attacks includes getting red and green energy balls from other Napses around it. Once it has obtained enough, it will shoot the energy balls at the bros. This attack is avoided by jumping. Touching the electric charges can lower their defense. This enemy can also multiply, but not as often as the Airnapse. However, when it multiplies, the Napse loses half of its remaining HP and its duplicate gets the other half of its remaining health. Napses take extra damage from fire, so the Fire Flower Special Attack is useful in taking them out quickly.
Mario & Luigi: Bowser's Inside Story / Mario & Luigi: Bowser's Inside Story + Bowser Jr.'s Journey
Names in other languages