https://imgur.com/a/eDHxriM

Only spawns at night (10pm-7am), click the link to see a picture of where to go, Behr Downstream node is targeted in picture, face towards it and the balls of light appear just in the clearing downhill. If it will spawn there will be a message pop up saying something about a sunset in the middle of the screen and balls of light will spawn that you need to go stand on, after a few lights it will spawn and you can kill it, good luck! (also a few more spawn locations near the scroll location between Phoniel's Cabin Entrance and Saunil Battlefield nodes but I did not have luck there)