Athena Saori watches over peace on Earth from Sanctuary and over young Kōga, until an invader causes commotion when he tries to kidnap Athena and the baby. Kōga is saved from certain death by the timely arrival of Gold Saint Seiya, who engages the mysterious invader, who reveals his identity as Mars. A new conflict begins as Seiya and Mars battle for the fate of Kōga, who years later, determined to live his life as he sees fit, challenges Athena.

Abzu tries to have Kouga under his control once more with no success and his attempts to kill Saori are stopped by his desperate efforts. Once feeling the radiance of his Cosmo, Kouga's friends send the last of their energies to assist him. Infused with the power of his companions and protected by Aria's light, Kouga manages to rescue Saori and destroy Abzu for good. As Earth regains the Cosmo that was siphoned from it, the planet returns to normal and the corruption that has spread into the Saints' bodies is washed away. After a brief encounter with Aria's spirit, ...