Lerdethak

The Lerdethak is a fictional creature from the Animorphs book series, specifically Animorphs #11: The Forgotten and The Hork-Bajir Chronicles.

The Lerdethak is a large creature from the Hork-Bajir homeworld, described as having a dark inner core, surrounded by a maze of snake like arms/tentacles. Through the arms/tentacles, a wide, drooping, blue-outlined mouth is visible.

Originally created by the Arn, the lerdethak is a genetically engineered creature, which lived in the zone of separation on the Hork-Bajir homeworld. Along with the lerdethak, the Arn created the Galilash, Gorks, and Jubba-Jubba, to deter curious Hork-Bajir from venturing into the lower valleys where the Arn lived. The lerdethak, and the other monsters, are controlled by mind-amplifier implants which are placed under the skin of the controllers scalp. Simple images as well as commands are sent to the monsters using this device.

The Lerdethak was one of the monsters used in the initial battle against the Yeerks on the Hork Bajir homeworld, led by Dak Hamee and Aldrea-Iskillion-Falan.

This is a morph possessed by Visser Three, though how he came to possess it is unknown.