Ceratosaurus was always the dinosaur with a little extra—literally—with an unusual (for a theropod) horn and eye-ridges that gave it a star quality that the larger allosaurus lacked. Small wonder then, that it’s been a staple of Saturday morning cartoons for decades. And now it’s ready to be imported into your game, again with another little something extra (blood rage) to make it stand out.
Technically plesiosaurus isn’t a dinosaur, but why be picky? Smaller than elasmosaurus, plesiosaurus adds a Lost World feel to aquatic encounters, from marshes to the open seas to deep underground in subterranean lakes and streams. Pathfinder’s version, while only CR 2, is a superior ambusher that makes quick attacks and then retreats (ideally with a gobbet of adventurer flesh in its mouth).
Ceratosauruses are typically pack animals, so when Serissa found an abandoned youngling, the druid took it upon herself to raise him. Now that the dinosaur is an adolescent, without a family group he becomes a target for bigger males who see him as a future rival. Serissa needs adventurers who can help guard her pet until he can fend for himself or escort him to safer territory.
A deep mountain lake moves back and forth in time. Locals know to avoid the crystal-blue loch, but a young boy new to the area goes wandering and vanishes. Adventurers who go to rescue him risk being attacked by opportunistic plesiosauruses until they find the boy…who, due to the vagaries of time travel, is now 16 and living in the care of band of prehistoric grigs.
Seeking to get close to a rival, adventurers pose as gladiators in the Yellow Sands Arena. The handler promises them a showstopping but secretly safe fight to help them build some notoriety. This arrangement is a setup, though. When the handler brings out the ceratosauruses the adventurers are to fight, he lashes the beasts with his scorpion whip to send them into a blood rage during the match.
—Pathfinder Bestiary 5 83