Poseidon is the Olympian god of the sea and the brother of both Zeus and Hades. Poseidon is one of the more vengeful gods, as proven when Cecrops selected Athena over Poseidon as the patron god of Athens, Poseidon then cursed Cecrops to roam the seas for eternity, though Athena blessed him with immortality so that he could find a way out, (which he did) Poseidon also cursed Ulysses while the hero was on his voyage home from the Trojan War. Ulysses was aided by Xena and Gabrielle (just like Cecrops) and eventually prevailed against the sea god He is the father of Antaeus, Triton and Polyphemus (in the myths he was the father of many others, but none where ever featured). He is the only god to be featured in the original XWP opening
Appearance Poseidon's appearance is strange, compared to that of the other gods, who are portrayed as looking (relatively) human about 95% of the time, Poseidon appears ONLY from the waist up, where he appears as a humanoid male, with a short beard, golden/bronze crown, matching trident (his trademark), and appears composed completely of water. It is unknown if this is his true appearance (which it was definitely not in the original myths), but some suspect it to just be a projection of himself (though his death in Motherhood would state otherwise), it is likely just an alternate form (like Ares Monster) he uses for convenience.
As an Olympian God, Poseidon possess immortality, shapeshifting, teleportation, sense enhancement, conjuring and a broad range of magical abilities. As the God of the sea Poseidon possesses complete control over the oceans. and all that inhabit it.
In the Xena Season 5 episode,Motherhood Poseidon was killed by Xena after being hit by a deflected fireball. His death reflects the theory that he was composed entirely of water, as he cried out in pain and evaporated into steam. He was the first of many Olympians to fall at the hands of the Warrior Princess.