16 HD Monsters

in OSRIC

• Aerial Servant - Creatures from the Elemental Plane of Air, invisible on the Prime Material Plane
• Albertosaurus - Much smaller cretaceous carnivore
• Archaeopteryx - Jurassic carnivore; no bigger than an ordinary bird
• Centrosaurus - Cretaceous herbivore that seems to have lived in very large herds
• Mosasaurus - Cretaceous carnivore that filled the same ecological niche as sharks