The Tunnel Blue spider is a small silver spider with claws so sharp, the tips seemed to disappear into thin air. It actually used its claws as teeth, pulping its meat before sucking it between its spidery gums. Its favorite method of destruction was from the inside, possibly when the victim is in some form of unconsciousness. A nest of them could take out a troll, quite a feat. One is more than enough for The People and, by extension, humans.

The spider is a hyperactive, finely tuned creature with a hair-trigger heart. When something as strong as coffee enters its bloodstream, it triggers a fatal heart attack.

It is used as a threat (against Major Evergreen, and Trouble Kelp), pet, and attempt at suicide in The Artemis Fowl Files by Turnball Root.