Gorgon

A Gorgon is a metal-plated ox-like beast which sometimes spews dangerous gas. Not to be confused with the Greek inspired s, such as Medusa. In its early appearances (Symphony of the Night, Circle of the Moon, Harmony of Dissonance and Aria of Sorrow), its breath had petrifying qualities. In Circle of the Moon and Aria of Sorrow, both it and its relative, the Catoblepas, had petrifying breath. In Dawn of Sorrow and later games, its breath changed to being poisonous, while the Catoblepas continued to use its petrifying breath.

It paces back and forth very slowly, occasionally stopping to belch its petrifying breath. Its back can be jumped on without taking damage. Its soul gives Soma the Body of Silver (CON +12) and Poison Breath in Dawn of Sorrow.

Castlevania: Symphony of the Night
The Gorgon's elemental resistances only apply to its body, which is protected with an armor plate. The head has no resistance to any form of attack.

Castlevania: Aria of Sorrow
Instead of covering its body with an armor plate, the game description depicts it as having a "hardened skin of iron". It may drop Meat Strip or Milk. It has no tolerances, but it's weak against Dark, Poison and Slashing attacks.

Just like its weaker twin, the Catoblepas, it's possible for Soma to stand on its back, thus avoiding its petrifying gas and also accessing areas which are too high to reach on your own.