Question: what is the t rex name in land before time

title: List of The Land Before Time characters
text: A Liopleurodon , dubbed a Sharptooth Swimmer , appears in The Land Before Time IX : Journey to Big Water . A resident of the Big Water , it is stranded in a body of water in the Great Valley after a large rainstorm . It then tries to eat Littlefoot and the gang , but it becomes trapped in a cave after an earthquake . After getting free , it relentlessly pursues the gang into the Mysterious Beyond , where they encounter it again . The Liopleurodon is lured away by Mo , who is apparently eaten by it , much to Littlefoot 's distress . However , they find Mo safe and sound , and he tells the gang of how he managed to hide from the Liopleurodon , after which it sensed the Big Water was nearby and swam away back to its home .