After the Triassic and Jurassic periods, there was one final era of dinosaurs to go before their eventual extinction: The Cretaceous period. 

The lands of the Cretaceous were now full of the most dangerous dinosaurs, with the famous tyrannosaurus rex being an apex predator. Other famous dinosaurs, such as the velociraptor and triceratops, also lived in the Cretaceous.

The sky still had the pterosaurs, but they had adapted across three eras to become horrifying hunters. The quetzalcoatlus, the largest flying animal of all time, became the most feared pterosaur of all time. It had a wingspan of 33-36 feet long.

The prehistoric oceans were not much safer. The plesiosaur still remained, but it had new competition at the top of the food chain. The mosasaurus was a ruthless oceanic killer featsing on plenty of fish and reptiles. Ocean levels were also far higher than they are now.

The Cretaceous era ended with one of the biggest extinction events the planet has ever known. A catastrophic asteroid struck the earth, wiping out plenty of species on impact and killing the rest due to disastrous changes to climate and shifts in weather, causing horrific natural disasters across the entire earth.

 This marked the end of not only the Cretaceous period, but an end to the dinosaurs. However, smaller mammals would end up surviving the cataclysm, and would end up as the new dominant species.