While Ben and Gwen argue about which of them gets to celebrate their next shared birthday on the actual date, they run into a kid named Gilbert who has fled from a summer camp. When Ben and company return him there they find that the camp has been mysteriously overrun by weird fungi, and that everyone else is gone except for two other campers. Now everyone must work together to stop the spread of fungi and figure out the cause.
Tropes
- Artistic License – Biology: Gwen mentions that she took a botany course when Ben asks why the fungus are after them and Ben comes to realize that "they want us, for plant food!". Fungi are not plants nor vegetation, and therefore would not be covered in botany courses, but are a distinct and separate Kingdom of organisms, whereas plants are organisms under the kingdom Plantae.
- Chekhov's Gun: Ben’s foot powder, which is used to kill the fungus monster.
- The Corrupter: Played for Laughs when Ben and Gwen’s arguing temporarily rubs off onto previously close twins Andy and Mandy.
- Foreshadowing:
- Grandpa Max gives Ben an athlete's foot powder that gets rid of all kinds of fungus. Guess what Ben uses to ultimately stop the main mycelium?
- Andy says that everyone gets athlete's foot at the camp. Ben later realizes they must have a whole supply of powder, which he and Gwen use to stop the puff balls from spreading spores.
- Fungi Are Plants: The fungus tries to persuade Ben in Wildvine form to join it due to being a "fellow plant".
- Girlish Pigtails: Mandy, the sweet and initially frightened only female camper to appear has pigtails.
- Half-Identical Twins: The only things that distinguish Andy and Mandy from each other are their hairstyles and their shorts. Mandy has Girlish Pigtails and while the two wear matching camp t-shirts, her shorts are red while his are blue.
- Logical Weakness: The fungus monster and its spawn can easily be killed by fungicides, making the athlete's foot powder that Max gives to Ben, as well as the supply of powder at the camp come in handy for killing the fungi monsters.
- Mr. Vice Guy: Andy and Mandy are very good at sharing with each other, without fail. However, later, this is to their disadvantage when the twins start to argue and ergo share the blame. Gwen has to call them out on it and say they don't have to share everything.
- Oblivious to His Own Description: As the twins easily share a blanket, Max comments that he knows a pair of kids who could learn from them. Cut to Ben and Gwen fighting over a towel and pausing to ask “Who?”.
- Plant Person: Ben gets another new alien, a plant-like being with extendable limbs and regenerative seeds growing out of its back that can be thrown as explosive projectiles. It is named as Wildvine in a subsequent episode.
- Took a Level in Badass: Andy, Mandy and Gilbert go from frightened campers to helping take on the mushrooms with sports equipment.
- What Happened to the Mouse?: It’s never revealed where the other campers and counselors fled, or even if they did get away.
- Zerg Rush: The mushroom zombies that keep attacking the heroes.
