A Promethean Surrounded is a side quest in Egypt (Act II). It is given by Inen, a woman and sorceress of the Order of Prometheus, found in a small monster camp in the northern Lower Nile region (before entering the Memphis Outskirts).
When approaching the camp, you will see some Dune Raider Assassins retreating back to it. Follow them to the camp and kill them. Talk to Inen after you defeated the monsters to complete the quest and get a reward.
Reward: 7500 Experience and a random magical necklace