Perseus was one of the founding members, human anyway, of the order and had managed to gather quite a few strong hero-like figures around him. The order was growing and was looked up to by the local people. Perseus had grand hopes for the extension of the order into all parts of the world and with this in mind he canvassed all the towns and villages in Greece to be considered their champion and protector. Soon he had a sizable army and they would travel all over the country sorting out problems and bringing to justice any criminal activity. Greece was a happy place to be.
The order flourished and it looked like it might well expand over all the earth. Then one day when the order were traveling along the sea shore Perseus realized that he had forgotten to take along a spare set of undies. Embarrassed he doubled back without telling any of his comrades. Well lo and behold while he was away, out of this sea comes this Medusa character. As ugly as sin and having an extremely bad hair day she was a formidable enemy.
The long and the short of it was they were all massacred. Not one was left. Perseus returned to the beach and found the order extinct except for himself. People began to gather on the beach and mumbling under their breath that Perseus must have ran away and that he was a coward. Perseus was too ashamed to reveal the real reason he had been absent when the attack took place. Persues, as is well documented in history traveled to the United Emirates and got himself new members of the order, filling them with revenge for their comrades at the hands or should I say the hair of Medusa. So although Perseus gets the credit for the killing of this brute ugly woman he had a lot of help from the order.