不久之前，我还相信巨齿鲨是大洋中体型最大的掠食者，直到我发现深海中的沧龙。 它虽然游速没有那么快，但体型和强壮度都远远超过了巨齿鲨，应该说沧龙才是整片深海的主宰者。成年沧龙能长到50英尺（15.24米）长，几乎比我至今遇到的所有海洋生物都要大。 沧龙是一种深海爬行动物，它会所有时间都潜入深海当中。毫无疑问，它是这个岛上最可怕的生物之一，当然也可以被认为是海洋中顶端的掠食者。
Common name: Mosasaurus
Species: Mosasaurus suspirita
Time: Late Cretaceous
Until recently, I believed the Megalodon to be the greatest of the ocean predators. Then I discovered Mosasaurus suspirita in the deeps. Not quite as fast, but much larger and stronger, the Mosasaurus rules the darkest waters off the Island. Growing up to 50 feet long, Mosasaurus is larger than almost every other aquatic creature I've encountered thus far. Mosasaurus is a deep-sea marine lizard which spends all of its time far beneath the water's surface. It is without a doubt one of the most fearsome creatures of the Island, and can certainly be considered among the ocean's apex predators.
Mosasaur has proven to be an excellent tame for the most advanced tribes. Due to its sheer size and power, you will often find tribes with bases and defenses built upon a Mosasaur's large "platform" saddle. Having one with you as an escort is probably one of the best oceanic defenses available!