Lacerta is one of Eris' pets and part of the constellation. He can stand on four legs, but can also stand on his hind legs.
In another scene, Lacerta and Scorpio were with Eris spying Sinbad and the trio through a martini glass. This is when Eris sends some sirens after them.
When Sinbad and his crew reached Tartarus, he and Marina entered Eris' lair. As they fall, Lacerta, Cetus, Leo, Musca, Scorpio and all of the other monsters watch them. Then, Lacerta, Musca, Leo and Scorpio surround them to attack, but only for Eris to send them away.
- When Lacerta stands on his hind legs, he resembles American Godzilla from the 1998 film Godzilla.