Primordial Cave is located behind the large waterfall by the Grand Knight statue and is part of the main questline Hall of Echoes Bound. Inside, you will find in one small area with a whole lot of chickens and a chicken rune which comes in handy for the High Hall quest The Runes of Wrath. In a larger area you will find 3 dragon statues, each of which requires seeds fed to it to let you pass. This gives you the quest Reaping the Seeds. After completing that quest, return and they will let you pass. You find a large room with dividing walls and small statue heads spitting fireballs. In a chest found on the left side of the room you will find a lever handle you need, after reaching that chest the statue heads behind you start spitting fireballs rapidly and you have to get out without getting too overly burned. At the other side of the room where the fireballs don't reach you will see a broken lever. Interact with it to fix it and then use it to disable the barrier ahead. After passing the barrier to a large cavern, a cutscene will trigger showing you where to go next. Here you speak with Patriarch to find out where the entrance to The Hall of Echoes is. After finishing your talk, go back up and Damian appears. 4 level 24 Black Ring Captains appear and you defeat them and can then proceed to exit the cave and continue on your way (you can use the Dragon Stone to bypass this fight after Damian leaves).
- Mindread the dragon to barely understand a little of the mighty dragon's mind, and you will recieve 4 Dragon Skill points.