Found her behind the large building at the back of Forgotten Shore. She spawns like the Sword Bearers used to. Like a mini public event. Just kind of hang out and watch for a ship to spawn at the back. A captain will appear to signal the start of the event. There are several waves of progressively stronger enemies. I took her down with 2 others. You could solo it but it'd be a challenge. You get a reward key for beating her. The key opens a chest which is located in random spots. You have 1:30 to find the chest so obviously the more people you have with you the better your chances of finding it. Rewards are random. I got a decoherent engram and some strange coins. Here's a video on it: https://youtu.be/UToK6CrFwDA *Update Drevis can spawn in multiple locations in the Forgotten Shore. You will receive a textual clue that she's coming.