The parasaurolophus is one of the most distinctive species of duck-billed dinosaurs. They will mostly leave PCs alone, but they make good companions and even mounts for certain exotic characters. The tylosaurus is a terrifying marine mosasaur PCs would do well to avoid.
A warren of elite troglodytes appears to have a back entrance, hidden among the rocks of a subterranean beach. Parties that attempt this route will find it guarded by a tylosaurus that surges out of the water to attack.
The services of a witch can be attained by bringing her a dozen parasaurolophus eggs—preferably without harming the breeding stock. To fetch them, adventurers must fend off the angry mother dinosaurs and the egg-eating wyverns that come to feast on the nests.
A saurian shaman (see Ultimate Magic) and her tylosaurus companion terrorize local villages away from a sacred spring. Despite her aggressive demeanor, her cause is noble: she guards the life of a dying nixie queen.
—Pathfinder Bestiary 2 91
GMs beware—since tylosaurus has a land speed (and is no slower than a dwarf), your players will try to convince you that their tylosaurus companion can go into the dungeon. They weighed 30,000 pounds. The answer is no.
Since parasaurolophus is a pretty standard hadrosaur, you an also use its stats for the lambeosaurus, corythosaurus, maiasaura, and saurolophus. But not the trachodon. That guy is taxonomically suspect.
Also, I hear he’s a douche.
Oh! Wikipedia tells me, “The family Hadrosauridae was first used by Edward Drinker Cope in 1869.” I may have mentioned this before, but one of my best friends lived for several years in Cope’s old house in Philly. There was a sign outside and everything. I pretty much lost my s--- with excitement every time I visited.
Man, now all I want to do is search the Internet for pictures of douchey trachodons. Seen any?
Oh (part deux)! Tomorrow is my birthday. Since it’s also my radio show (10–noon, U.S. Eastern), why not celebrate with your ears?