Tyrannosaurus Rex lived throughout what is now western North America in the Maastrichtian age of the upper Cretaceous Period (not the Jurassic, no matter what Chrichton and Spielberg say). He was the largest carnivore around, and is usually depicted as preying on triceratops and others, though some argue he was more scavenger than predator. T Rex's were first discovered a little over a century ago, it seems that there are about 30 or so known specimens, including about 15 skeletons that are more complete. That was surprisingly low to me, but looking at what various paleontologists have written, that seems to be a pretty rich sample size. According to Mahjqa and Steve Demlow there is a complete skeleton just a few feet underground in this LEGO city (Mahjqa designed this, Steve built it). You'd think those LEGO guys would dig it up, as Sue (the largest T Rex found, just over 20 years ago) was bought by the Field Museum in Chicago for over $8 million.