It was an actual weapon used by the Byzantine Empire, which controlled Greece since Theodosius (Roman Emperor) and soon before the fall of Constantinople. Because of its effectiveness, similar fire-based weapons used by other empires alluded to Greek fire. Greek fire was a very dangerous weapon for the mortals that used it, and for the enemies. There were two types of Greek fire. The first one was a mixture of chemicals. The second was made by reflecting light off many polished shields (metal) or mirrors. Archimedes was the one who supposedly made Greek fire with mirrors. Mythbusters proved this can be done on their show. The chemical Greek fire was a lot more dangerous to make. Archeologists still have not yet found the recipe for it due to the fact that it was a well kept secret. Even the different people who assembled the concoction only knew certain ingredients not all.
Greek fire burns green and can be made used as bombs. Greek fire can also burn underwater as shown in The Last Olympian when Percy goes to Poseidon's underwater palace. Greek fire is described as a swirling green liquid that explodes if dropped on the ground and the container is broken. It is also used as a decoration for Hades' cabin at Camp Half-Blood.
Charles Beckendorf used Greek fire to blow up the Princess Andromeda, in order to slow down Kronos on his invasion of Mount Olympus. Percy escaped, but Beckendorf sacrificed himself. The Hephaestus campers also used Greek fire to defend the Holland Tunnel during the Battle of Manhattan. Later, before Percy battles Hyperion, the Titan is hit by a Greek fire bomb as he crosses the water. It as no effect, however, as he opens his palm and sucks up the flames.
Luke Castellan, Thalia Grace, and Halcyon Green create a vial of Greek fire using ingredients found in Hal's room. They are successful in creating the deadly fire and Hal uses it to destroy the leucrotae evidently causing his death and allowing Luke and Thalia to escape.
Leo Valdez stocked the Argo II full of vials of Greek fire for the trip to Greece. When the Skolopendra attacked the ship Leo managed to throw a vial of Greek fire down the creatures throat, scaring it away.
- Pitch from old torches
- A catalyst (electricity)