[Kurona]

Well, coming from my theory that these are chosen based on what would work aesthetically...


Hibiki - Tiger. The markings on his helmet and 'gloves' lend themselves well to stripes, while the light chest armour works as fur.

Agito - Triceratops. Mostly due to the horns on his head, and other 'spiky' parts such as his shoulderpads.

Amazon Omega - Spinosaurus. A pretty brutal and deadly creature with defining 'sharp' features.

Stronger - Whale. Stronger has a 'large' appearance to him due to the chestpiece and larger helmet; and his horn could work very very well as a water spout.