Mosasaurus is a prehistoric reptile that coexisted with the Dinosaurs. A version has appeared in two LEGO themes; in the Dinosaurs line as 6721 Mosasaurus, and as a creature in the Jurassic World line exclusive to the video game LEGO Jurassic World. It also made a small appearance in LEGO Dimensions as part of the Jurassic World franchise.
Mosasaurus appears in the video game LEGO Jurassic World. It is depicted with dark blue skin and a gray underbelly. It also lacks a tail fluke and moves in a snake-like motion like older restorations. This probably because there is no LEGO element at the time that resembles a mosasaur tail fluke.
The Mosasaurus first appears in the level "Under Attack" where it eats Zara, like in the Jurassic World film. The second appearance of the Mosasaurus is in the final cutscene to the level "Main Street Showdown" where it lunges out of the water and grabs the Indominus. The Mosasaurus' final appearance in the game's story is in the end cutscene to the Jurassic World levels where it is seen swimming under the helipad that carried the chinook that Dr. Henry Wu escaped in as the Indominus rex, Zara, and several Jurassic World workers play a game of cards inside the Mosasaur's stomach.
Its amber, as well as the boneboxes that construct its skeleton, are found in the level "Main Street Showdown". Its amber is found in the Hammond Creation Lab to the left inside the Innovation Centerthat has an InGen panel for a lock that can only be opened by characters such as Simon Masrani or John Hammond and is found in the "Extraction Room" where a character who can access a hand scanner can free it from its glass case. The Moasasaurus can only be spawned in the Underwater Observatory.
As a playable creature, the Mosasaurus is able to let out a low roar that can smash amber bricks like large theropods, such as Tyrannosaurus rex can do.
In LEGO Dimensions, the Mosasaurus appears in the Jurassic World hub world. The crane used to feed it can be purchased for the dimension, which the player can activate. Unlike in the previous LEGO game it appeared in and Jurassic World it is fed a turkey rather than a shark. The model for the Mosasaurus in the game is reused from LEGO Jurassic World.