So I was patrolling the dreadnaught and came across some taken spawning then just disappearing then re-spawning again over and over and over. They drop blue engrams and sometimes legendary and it's a taken knight and a taken acolyte in the hall of souls to the left of where you face to challenge the court of oryx, that bridge there. Idk if this is a thing or just a one time event or idk. Feel free to confirm I've gotten video but it hasn't uploaded yet will post as soon as possible Edit: Video is now on YouTube https://m.youtube.com/watch?v=HIHV3kqqjyA