Details
Ankylosaurus was a four-legged plant eater. To protect itself from preditors its whole upper body was covered with bony armour. It also had bony plates sticking out of its back. The head was also heavily armoured and was as wide as it was long. Short powerful legs would have given ankylosaurus the ability to move at speed.
At the end of the long tail was a bony club. It is likley that ankylosaurus was able to swing this at speed to help defend itself from attackers.