Magnacore

Known as the Katastros by the Greeks (Magnacore being it's Roman name), the Magnacore is indeed a fearsome beast. Legend tells of it being the offspring of the Nemean Lion and a Manticore, and when both were killed, was raised by the Chimera.
The Magnacore was quick, strong, ferocious, and more than a little bit cunning. It's mouth could partially unhinge, much like a snakes, and this allowed it to deliver a punishing bite to any enemy, using it's triple row of extendable teeth to eat anything or anyone it came across. It's spikes gave it extra protection, and even it's hide was incredibly difficult to pierce, though not invulnerable like it's father's. It could shoot spines from it's tail, which were filled with a poison that would disorient a foe, quickly followed by paralysis. It could fly quite well for such a large beast.
However, it's most deadly weapon was a deadly smoke that it would breathe from it's three heads. The smoke was pitch-black,unable to pierce with any light, though the Magnacore seemed to be able to see through it. The smoke took incredibly long to dissipate, and simply wouldn't as long as the Magnacore kept breathing it. The smoke contained a small amount of the poison found in it's spines, and would disorient the victim even further than the clinging blackness of the smoke. The Magnacore, being surprisingly stealthy and silent, would then stalk it's prey through the smoke, attacking from the shadows unseen.