Iguanadon (i·guan·o·don)

Threat Level: Medium

Although iguanodons typically walk on all fours, they can stand on their hind limbs and move around for a few minutes at a time. This behavior has only been observed when protecting themselves from predators. While this does expose their underside to attack, iguanodons have a useful weapon. The thumb of their front limbs is a spike of solid bone, and is a formidable weapon of defense.