The team investigates the appearance of strange creatures, who have come out of the ground and can eat rocks. As they unravel the mystery, it turns out Vulkanus is behind it, wanting to drop a bomb to the center of the Earth and make it more like his homeworld.
- Ax-Crazy: Mouldywarp’s way of preventing Vulkanus from trying again? Blow up a whole supply of TNT.
- Costume Evolution: In his appearance back in season 1, Vulkanus' armor was more of a green-ish colour. Here, it becomes blue, which persists for the rest of Alien Force and Ultimate Alien.
- Dynamite Candle: Kevin lights a stick of dynamite, thinking that it's a candle. After Gwen blows it out, he tries again, and Ben blows it out. Gwen then lights up the room with her mana.
- Fantasy Kitchen Sink: Discussed. When the team contacts Grandpa Max, he says the strange creatures are native to Earth, as are unicorns, trolls and other fantasy creatures. Except Bigfoot. That's a guy in a suit.
- Full-Body Disguise: To hide his mutation from people outside of his friends and family, Kevin has taken to wearing a ID Mask.
- Hostile Terraforming: Vulkanus plans to terraform Earth into a replica of his home planet, where a cool day is 850 degrees Fahrenheit.
- Karma Houdini: While his plan is thwarted, Vulkanus can’t be legally punished by Ben and co since he owns Earth and has full rights to do whatever with the planet.
- One-Shot Character: Mouldywarp, who lives underground and is the owner of the Pyroxivores, only appears in this episode.
