Question

Greek fire was used by the

Answer 1

(Not sure if this is a good legit answer) In mythology, the greeks would use fire as a symbol used by a god, the god who stole fire to give to humans when the *universe* was being created.
(I hope this helps not 100% sure)

Answer 2

Greek fire was an incendiary weapon developed c. 672 and used by the Eastern Roman (Byzantine) Empire. The Byzantines typically used it in naval battles to great effect, as it could continue burning while floating on water. It provided a technological advantage and was responsible for many key Byzantine military victories, most notably the salvation of Constantinople from two Arab sieges, thus securing the Empire's survival.