The edmontonia was a type of ankylosaurid dinosaur. It was a massive, armoured creature, over 20 feet long and over 4 tons. It was covered in a tough plating and had long spines projecting from its shoulders. It also produced a foul smell. The edmontonia lived during the late Cretaceous period.
The edmontonia was one of the species that the Silurians brought back from extinction after they took over in a parallel world. An edmontonia was the first creature the Seventh Doctor and Ace encountered after crashing the TARDIS into this world. This edmontonia thought the Doctor's TARDIS was a threat and knocked it into a tar pit. (PROSE: Blood Heat)