In the Squawk Role-Playing Game, Manticores are intelligent ceratopsian dinosaurs. While most ceratopsians, like Psittacosaurus and Triceratops are stocky quadrupeds, Manticores are gracile bipeds with long limbs and very long tails. Manticores lack the long horns of some of the larger ceratopsians, and they have a proportionally longer neck shield than any other ceratopsian. Manticore legs are adapted for running, with only three toes on each foot. The hands are four-fingered manipulators with opposable inner and outer digits. The long tail is a specialized weapon with the tip partially fused into a hard, sharp weapon. The manticore idea is based on creature ideas from RPGs we made before Squawk. Manticores weren't always dinosaurs (and they weren't always called manticores - the original name was unpronounceable by humans.) The beak is a recent addition to make manticores more like their ceratopsian cousins. As the picture above shows, we have been toying with the idea of giving manticores elongated protective scales.
In the Squawk role-playing game, "dragon" is a common name for four-legged predators. Because the big predators in Squawk are archosaurs, most dragons have a classic "reptilian" shape like the crocodile above, and many of them are equally at home in the water or on land. I like to call this critter the "catoplebas". The forelegs are probably much too long compared to the back legs. Most archosaurs have longer hind legs and higher hips than shoulders. (Obvious exceptions would include high-shouldered sauropods like Brachiosaurus, and some birds.)
Strange as it may seem, crocodiles are more closely related to birds than to lizards. Birds are dinosaurs, and some dinosaurs have toothy snouts, long tails, and scaly armor like crocodiles, but it's still hard to see the bird-crocodile connection because (modern) crocodiles are specialized for living in water (a bit like archosaurian otters.)
It's easier to see the kinship between crocodiles and dinosaurs (including birds) when we look at the different ways that crocodiles move. Like lizards, crocodiles can crawl on their bellies, but when crocodiles need to walk a long distance, lift their bodies off the ground or move quickly, they can use the "high walk" and "gallop", which are very different from the ways lizards walk and run. (This video was posted on YouTube by crocodilian.com.)