Tyrannosaurus Rex, or T-Rex, was the most feared and vicious species of its time.
One of the biggest meat eaters ever, this top predator stood up to 13 feet (4 meters) tall up to its hips and could reach some 40 feet (12 meters) long. Want weight? How about 9 tons?
Its name translates to "king of the tyrant lizards," so you know the hulking beast meant business, even though its tiny forearms seem a bit less than fearsome.
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T-rex had longevity on its side, too. It was among the last of the non-avian dinos in existence before mass extinction sent the dinosaur era into history.
Here, thanks to CGI, we see these top hunters in attack mode -- taking down prey species, and sometimes even other Tyrannosaurs.
It could not have been fun to come up against one of these kings of the dinosaur era.