Allosaurus

Allosaurus (“different” dinosaur) was a fearsome predator.
When food was scarce, it simply turned to carrion. The Allosaurus had 40 jagged saw-teeth in its upper jaw and 32 in its lower jaw; the individual teeth could measure up to ten centimetres in length. If a tooth broke loose, another grew in its place, as with all reptiles.
Fossilised footprints reveal that the preferred hunting grounds of these carnivorous dinosaurs were waterholes, where they lay in wait for herbivores.

Length: 12 m
Weight: 2 to 3 t
Period: Late Jurassic to Early Cretaceous (150-99 mill. years)