The Greek goddess Athena (spelled in Greek as Ἀθηνᾶ and Ἀσάνα, in the manga and the anime adaptation respectively, and occasionally as Ἀθάνα in both) is the goddess of wisdom and heroic endeavor, and daughter of Zeus. In Kurumada's mythos, she is sent to Earth by the Olympian gods every 250 years, when evil takes over Earth. Her mission during every one of her incarnations is to restore peace and bring hope, destroy the agent of evil and protect Earth; to do so, she has been assisted since the ages of myth by an army of 88 youths of great strength and courage, whose fists rend the skies and whose kicks split the earth, don radiant holy armor called Cloths, and are known as the Saints of Athena. Athena is said to be by birthright the goddess of battle, but she didn't believe in conquest and only fought defensive wars. She hates weapons, and thus only allows her Saints to battle using their bodies and armors. The only Saint allowed by her to wield weapons is the Libra Gold Saint, and it is only with her permission that the Saints are allowed to brandish the weapons kept by the Libra Saint. She has opposed the ambitions of antagonist deities since the ages of myth in Greece, earning herself the rejection of the other Olympian gods. She has had specially a long-standing conflict with the god of the Underworld, Hades.
Since she is a deity, Athena has capabilities that surpass humans by far. She is a frail young woman untrained for battle, mostly unable to fight physically, but her Cosmo is immense, and surpasses human Cosmo infinitely. She is a being of total compassion and love, and she will stop at nothing to protect Earth, the world she cares about so much, and its living creatures.
Athena has great endurance to pain, unfailing courage and persistence and unbreakable willpower, greatly augmented by her full trust on her Saints. As Saori, she possesses a brilliant intellect, she's also a capable money handler and strategist, as she is the head of the Graad Foundation and has been ever since Mitsumasa Kido's death. In fact, before Saori came to know she was Athena, she had become a very successful and admired businesswoman in her own right.
Athena's attributes include Nike, the goddess of victory, represented as a golden staff she always holds in her right arm, and the Ægis shield, impervious to any kind of attack. Also, as a goddess, she is capable of donning her powerful Divine Cloth, which rests in the form of a giant statue in her image at Sanctuary until it is revived with her blood.
Athena has also exhibited great mastery of her Cosmo, as she is able to use it to generate abilities with various effects. She channels her Cosmo mostly through her body or through her Niké Staff. Both in manga and the anime adaptation, several techniques have been revealed: Healing auras (she's said to be the most powerful healer in the Saint Seiya universe, able to heal even lethal injuries if summoned just in time), defensive shields, teleportation (in the conclusion of the Poseidon arc and Hades arc), the Seal of Athena (used on both Hades and Poseidon to seal them away), and Misopethamenos, a divine gift bestowed upon Libra Dohko. Her Niké Staff can be used as a weapon when Cosmo is channeled through it, becoming a piercing weapon, in the same way she used it to kill Hades.
Athena also managed to awaken her Cosmo to the Eight Sense, thus being able to descend to the underworld without being subject to its laws.