The son of Poseidon and Gaia in Percy Jackson is Antaeus. He appears in the Riordan mythology setting as a giant who is the child of Poseidon and Gaea, and he is known for being especially dangerous because he regenerates when grounded.

Quick Scoop

  • Name: Antaeus.
  • Parents: Poseidon and Gaia/Gaea.
  • What he is: A half-giant from Greek mythology used in the Percy Jackson world.
  • Not to confuse with Percy: Percy Jackson himself is Poseidon’s son with Sally Jackson, not Gaia.

In context

In the series, Antaeus is referenced as one of Poseidon’s more brutal offspring, tied to a myth where his power depends on staying in contact with the earth. That makes him a very different kind of child of Poseidon from Percy, who is a demigod hero rather than a giant.

Tiny note

A lot of fandom discussion mixes up Poseidon’s children or adds fanfiction versions, but in the canon-style references the answer is Antaeus.