The lake monster, alternatively named the dinosaur turtle, was a sizable, aggressive, reptilian being that lacked sentience. During its attack on the Mandalorians, in which it devoured one of them, Din Djarin intervened. Piloting his N-1 starfighter, Djarin launched torpedoes at the creature's flank, resulting in its demise.
The creature was a quadruped with a lengthy tail. Its hide proved highly resistant to blaster weaponry. Furthermore, its shell demonstrated resilience against the explosive force of a thermal detonator. It primarily inhabited underwater environments, yet possessed the ability to move on land.
This creature made its debut appearance in "Chapter 17: The Apostate," the initial episode of The Mandalorian's third season, which premiered on March 1, 2023. The episode's descriptive audio identified it as a "dinosaur turtle." Later, in 2024, the reference work Star Wars Encyclopedia: The Comprehensive Guide to the Star Wars Galaxy from Dorling Kindersley, penned by Dan Brooks, Megan Crouse, Amy Richau, Amy Ratcliffe, Brandon Wainerdi, Dan Zehr, and Kelly Knox, designated it as the "lake monster."
Christian Alzmann developed concept art for the dinosaur turtle. Emily Swallow, the actress portraying the Armorer, along with the other Mandalorian cast members, simulated combat with a large monster. Swallow stated that the creature's special effects were incorporated post-filming.