The Underminer's motivation is to show his existence.
The Underminer was killed when jumped on top of unfinished head part his robot creation in which he was on top of into his lair which exploded and destroyed his robot army ending his plans. (Only game-canon)
In the comic series, The Underminer makes an appearance in the "Terror from Beneath" story arc, in which he briefly allies with Dash to fight off alien invaders. However, the appearance is revealed to be part of an extensive hypnosis-induced dream. He later makes an actual appearance as a member of the Unforgivables, the criminal alliance headed by Xerek. As part of a plan to ruin the reputation of the Incredibles, Underminer is given control of a giant robot painted in the Incredibles' colors and rampage through Metroville. Xerek later eliminates Underminer upon completing his purpose.
- Some fans speculate that the Underminer is actually Gilbert Huph (or even a possible relative of Huph's) out for revenge, (due to their similar facial features, personalities, height, hate/disregard for all mankind (Bob Parr being no exception) etc.) but its most likely not since the Underminer has mole-like teeth and just pop out of Nowhere.
- Humorously, both Huph and the Underminer's respective voice actors both starred in the Toy Story series as Rex and Hamm respectively.
- The Underminer (in keeping with the tradition of having most of the cast be based off of Marvel characters), is likely based on the Mole Man who was the very first known villain of the Fantastic Four.
- The Underminer was planned to appeared in Disney INFINITY but was scrapped and only was seen in concept art although he does not actually appear in the game. However, customizations for buildings based on The Underminer can be unlocked in The Incredibles Playset.
- The Underminer re-appears in Disney INGINITY: 2.0 Edition, once again as concept art.
- Its possible why he could of been removed in Disney INFINITY for his removal is that he only appeared at the end of the movie, making him a somewhat obscure character compared to Syndrome, who would be more of a draw for those considering buying the game.