• Neptr is a robot built by Finn in "What is Life?" Origionally programmed to "throw never ending pies, FOREVER," Neptr comes to life when struck by lightning. However, it is not enough power to run him efficiently. Finn uses some balloons that owe him a favor and they sneak into the ice kings castle, where a blast from the Ice Kings "Iceapede" brings Neptor up to full power. This also gives Neptr a father-son link with the Ice King. Neptr chooses Finn over the Ice King though so he can initiate his original programming and get Jake back for his butter prank on Finn.
  • In the end credits for "What is Life?," Neptr is listed in the credits as "N.E.P.T.E.R."
  • It is unknown where Neptr gets the ingredients for the pies he makes, possibly generating them spontaneously through magic rather than machinery.
  • Neptr is like the monster from Mary Shelley's Frankenstein as both are brought to life by lightning and are made from salvaged non-living parts.
  • In a sneak peek of "Hot to the Touch," Neptr's name was spelled "Neptor" which is his name in the Spanish version of the show.
  • "Hot to the Touch" contains Neptr's first song, "Working for the Master."
  • Neptr returns in "Hot to the Touch," where it is revealed that he was hiding for 15 months, 4 days, and 9 hours in a game of Hide and Seek that was accidentally forgotten by Finn and Jake