Napstaton is the Underswap version of Napstablook. Napstaton loves music but misses Mettacrit. In the Neutral and the Pacifist Route, Napstaton turns into Napstaton EX, while in the Genocide route, Napstaton NEO.
Rather than Mettaton and his legs, Napstaton prizes his arms.
Napstaton's original form is near-identical to the original design of Mettaton but with a teal screen and an N instead of an "M"
Napstaton is very similar to Mettaton's classic form but with a backward hat, a hoodie and has a color theme of blue instead of pink. He is also sometimes depicted with floating sound mixers. He has a blue heart or "soul" instead of a pink one and also has both eyes showing. He also is depicted without his legs connected together.
Neo Form (Photo Not availiable)
Napstaton Neo is also similar to Mettaton Neo. He has bigger sound mixers, a backward hat again, and his theme is blue. His eye changes into a blaster and the other eye is glowing.
- Undyne: Undyne built Napstaton as an entertaining robot for genocide, but when seeing the protagonist, she decides to remove the Genocide part and put acting, but it was already a nice robot so she didn't need to remove any genocide. In Genocide, Undyne gave him the Neo look but it wasn't completed during the protagonist's appearance. Napstaton goes down in one hit after this.
- Happstablook: Happstablook is Napstaton's cousin. Happstablook is said to be Mettaton but in their original ghost form.