- Narrator: Rachel
The Animorphs discover a new potential weapon to use against the Yeerks.
Tropes:
- Alien Catnip: Instant maple and ginger oatmeal can permanently replace Kandrona for Yeerks, at the cost of making them go insane and losing control of their hosts. It's highly addictive.
- Attack Drone: The Yeerks now have hunter robots for the purpose of vaporizing any animal that managed to get into the Yeerk pool.
- Buried Alive: When escaping the Yeerk pool, Rachel uses a stolen Dracon beam to cave in a tunnel, burying the team. They use their mole morphs to escape before the Yeerks can dig them up.
- Claustrophobia: Rachel starts suffering this once she gains control of the mole's instincts, as her human mind doesn't care for burying herself underground.
- Drugs Are Bad: The Animorphs directly compare the Yeerk's addiction to instant maple and ginger oatmeal to drugs. The Yeerk hierarchy treats it the same way, with instant maple and ginger oatmeal being banned and anyone caught with it being punished for rule-breaking.
- Intoxicated Superpower Snag: It's discovered that the Yeerks are chemically susceptible to maple-and-ginger flavored instant oatmeal, which they treat as a highly addictive drug on par with crystal meth. Furthermore, the negative side-effects also result in afflicted Yeerks intermittently losing control of their hosts during their demented frenzies, hence how the Animorphs found out about this in the first place.
- Metal Detector Checkpoint: For lack of a better trope. The Gleet Biofilters are stolen Andalite technology that fries any unauthorized DNA trying to get in or out of a location. Humans, Hork-Bajir, Taxxons, and Yeerks can get past, but flies and cockroaches can't. The fact that all Yeerk pool entrances now have one forces the Animorphs to find another way inside.
- Tunnel King: Because the Yeerk pool entrances have higher security, the Animorphs acquire moles to dig their way inside. It takes them a week of digging to get to an open space underground.
