Orthros is a boss in the Dawn of Souls and succeeding versions of the original Final Fantasy. He is found in the Whisperwind Cove, and must be fought in order to reach the end. He is Ultros, a recurring boss from Final Fantasy VI. The onomatopoeia of Orthros's laugh ("Uwee hee hee!") is the same as Kefka's iconic laugh from the same game.
Orthros is probably a bit easier than the preceding boss, Typhon, as he lacks any moves that can inflict Instant Death, so NulDeath is not a priority. His physical attacks, while quite powerful, should not trouble any party with Protera cast on them. He has a fairly high amount of HP, but his Defense stat is unimpressive compared to the other Whisperwind Cove bosses, so physical attacks can be used to full effect, and can be powered up with Haste, Saber and Temper.