Spinosaurus
Spinosaurus was potentially the largest theropod dinosaur ever to have lived, beating out even Tyrannosaurus Rex and Giganotosaurus. The creature's most distinctive feature was the sail that rose from its back, supported by spines of bone. It was likely that the sail was mostly used for courtship displays and intimidation. Spinosaurus spent equal amounts of time in and out of the water, though it is primarily a land-based creature.
Spinosaurus was an opportunistic predator, mainly preying on fish, but happy to kill and eat anything that crossed its path. The creature was extremely territorial, and would hunt down and kill anything that entered its territory. Unfortunately for most creatures, Spinosaurus was quick to stake out new territories and rarely took the time to check if there were already residents. (PROSE: Prehistory Repeating Itself [+]Loading...["Prehistory Repeating Itself (feature)"])