Marf's behavior takes a destructive turn for the worse, forcing Robot and Monster to institute emergency pet training. They each draw on their personal strengths to devise training methods for their beloved pet, only to discover he may not be all that he appears.
- Monster - Harland Williams
- Robot/Marf/Narf - Curtis Armstrong
- Ogo - Jonathan Slavin
- Perry - Maurice Lamarche
- Mr. Wheelie - Kurtwood Smith
- Master Grabmirist - Ping Wu
- Dog Lady - Carol Ann Susi
- The title is an obvious parody of How to Train Your Dragon.
- The scene where Robot dodges metal objects attracted by his Fetcher's magnet is used in the series' intro.
- Goof: At the end of the episode, Monster's hat disappears.
- Before leading toward the ending of the episode where Robot and Monster find out that the pet they had thought was Marf the whole episode was actually Narf, in the beginning, when they find "Marf", the identical pet actually utters its name 'Narf' when Monster found him they didn't recognize a difference.
- The name Narf is a reference to the catchphrase uttered by Pinky from the Animaniacs' segment Pinky and the Brain.
- In this episode, it's been hinted that Ogo's Birthday is in December because he mentioned his birthstone being Turqouise, Turqouise is the birthstone of December.
(watching Marf continuously doing his business)
Robot: (to Monster) How many treats did you give him?
Monster: Uh, 8? (pauses) 156? Why?
(both are engulfed by a massive wave of bolts)
Narf Lady: You guys are INSANE!