Chimeras have fallen in stature since Bellerophon’s day. They’re almost no adventure’s boss monster, being relegated instead to wandering monster/side trek duty or the gladiatorial pits. Three things perk up the chimera’s potential, though. 1) The different-colored dragon heads could suggest regional/species differences or ties to draconic forbears. 2) While they rarely speak, that doesn’t mean they never do…and the fact that they can (and what they might say) could surprise a party that knows Draconic. Finally, 3) few adventures play up the fact that these are, in the words if the Bestiary, “monstrous creatures born of primordial evil.” Perhaps chimeras reflect the displeasure of the gods in some way, or are drawn to (or even arise spontaneously from) sites of evil and insult. The presence of a chimera, instead of being a sideshow, could instead by the sneak preview of a larger drama.
Maleffin the Azraq, blue dragon suzerain of the Three Pleasant Lands, loathes the similarly colored chimeras that roam the wastes in her domains—evidence of some long ago blue’s rutting that she finds distasteful. Nevertheless, blood is blood, and she demands the heads of anyone who harms one of them.
In the veldt, sleek leopard- and green-dragon-headed chimeras are more common and slightly more agile than their leonine cousins. Occasionally one appears with a brass or copper dragon head instead. These tend to be no less evil than the chromatic variety, but they are more talkative…and sometimes willing to parley or trade information for a fat herd animals.
A usurper sits on the Rose Throne, having killed not only the royal line but also the bishops who refused to confirm him. Now a chimera stalks the land, devouring a member of his retinue every solstice and equinox. If the chimera is killed, a new one arrives at the next solar event.
—Pathfinder Bestiary 44