Aristides Demetrios, alias the Olympian is a hefty Greek man who wears the mystical Golden Fleece, which grants him the strength of Hercules in addition to various other powers connected to the heroes who were counted among the Argonauts. He is recruited as the representative for Greece in the Global Guardians. Whilst in service with the team he helps Superman stop the gathering of mystical artifacts designed to bring back the villain Thaumar Dhai. They encounter Echidne, an old adversary of the Olympian, a beautiful woman with a long, gigantic snake form instead of legs. Olympian would later join Superman and many fellow Guardians on Easter Island. They would again battle Echidne and her her fellow mystics. Dhai's mystical return is reversed and he is seemingly destroyed..  The Greek hero later meets Fury of Infinity Inc.
Olympian protests when the original Icemaiden, leaves the Global Guardians because of her feelings of inadequacy. When he learned that his fellow members of the Global Guardians were to be supported by the Bialyan dictator Queen Bee, Olympian joined up. An unwitting participant in a public relations ploy, the Olympian helped his teammates and Justice League Europe battle a giant, alien robot on the grounds of the League's embassy. This robot was sent by the Queen Bee herself, using technology stolen from a now-dead member of the alien Dominators. The Queen did not care if the robot ended up killing any of the Guardians. The Olympian and Godiva help save nearby confused well-wishers from being crushed when the damaged robot threatened to fall on them. After the Queen Bee died, her successor diagnosed Olympian with schizophrenia and arrested him. He later reunited with the other Global Guardians and has remained a member since. 
A romantic relationship with Dora Leigh (Godiva), his teammate in the Global Guardians, is interrupted when an ancient villain named Fain Y'onia attacks the duo in London. A brief battle with Fain Y'onia leaves them both injured and Godiva apparently powerless. Other Guardians were rendered powerless by the villain and Bushmaster was slain. The Olympian rallies with the able-bodied members of the Guardians and ambushes Fain in the Arizona desert. During the battle, Tuatara is badly injured and Thunderlord is slain. The Wild Huntsman and Fain Y'onia vanish from this reality. The Olympian is the one who theorizes that the Huntsman's final purpose was to do exactly that and that both will return one day. 
The Olympian is later seen as a member of the Ultramarine Corps. He also appears in a failed attempt to gain the aid of the Spectre. The Olympian returned as the guardian of Cassie Sandsmark and her mother Helena, a position appointed to him by Zeus.
- Mental Illness: Prolonged use of the Golden Fleece has had an adverse affect on the Olympian's psyche. Through it, he has become influenced by the personalities of ancient warriors and has inherited their need to boast.
- Golden Fleece: The Fleece gives him the powers of the Argonauts. These include:
- Flight: from Kalais, sons of Boreas, ability to soar into the skies through an act of sheer will and could hover completely still or effortlessly achieve sub-orbital levels. With his agility combined, he could travel across planet in blinding speed.
- Superhuman Strength: from Heracles, the wearer possesses incredible physical strength, being able to lift at least 100 tons on a normal scale and could effortlessly break through heavy material and manipulate heavy objects.
- X-Ray Vision: from Lynkeus.
- Superhuman Speed: from Atalanta, capable of reaching incredible speeds, exceeding up to Mach 10, the wearer also has superhuman senses such as agility and reflexes.
- Enhanced Intellect: from Admetus, this ability provides him heightened superhuman comprehensive knowledge of all aspects including mathematics.
- Telepathic Immunity: from Peleus, able to see through illusions, and has a greater resistance than most to mind-control. However, he is more susceptible to pheromone-based mind control.
- Self-Sustenance: from Hylas.
- Teleportation: from Zetes.
- Metamorphosis from Poriclymenus.
- Invulnerability: from Kaineus.
- Accelerated Healing: from Meleager.
- Poison Immunity: from Staphylus.
- Longevity: from Euryalus.
- 28 Appearances of Aristides Demetrios (New Earth)
- 5 Images featuring Aristides Demetrios (New Earth)
- Quotations by or about Aristides Demetrios (New Earth)
- Character Gallery: Aristides Demetrios (New Earth)