Earthen Root Enclave Dungeon Guide ESO

Lutea is a Nereid secret boss who first has to be activated by completing a puzzle in the second area of Earthen Root Enclave (just after you go underground after defeating the Corruption of Stone). If you defeat Lutea, you will get a buff called Lutea's Rejuvenation which increases your magicka and stamina recovery by 30%.

How to Activate Lutea

There are three pools of water scattered around the cave system. You can see them on the map as green pools. To activate the boss, you will first need to defeat the spriggans who are guarding these pools. Their heavy attacks hit quite hard, so the tank will need to taunt them. After defeating the spriggan guardians, go into the water and you should get a synergy to fill a vessel. Activating this will give you a speed buff, and you will then have 60 seconds to find a large glowing flower. These flowers will also be guarded by adds. As long as the timer didn't run out, you will be able to use the synergy again on the flower to give it the water that you just picked up. The flower will then open and several smaller glowing flowers will sprout, signalling that this part of the puzzle is complete. There are three pools and three flowers, and you need to do this for all of them in order to activate the boss. Once activated, you can find her back near the beginning of the cave system, where you initially entered from.

How to Defeat Lutea

Lutea has around 3 million HP. 

Water Jet

Her first mechanic will be to attack players with a jet of water. You will get a visual effect on you for a few seconds before this happens, so when you see this you should start blocking. 

Ice ring

She will then teleport away from the middle of the arena, and summon a "donut" shaped ice AOE to trap players inside. It is safe to stay in the middle of this though, just don't stand in the ice. 

Water Throw

Periodically she will also throw water in front of her, which does quite a lot of damage to anyone stood in the way but isn't enough to one shot you. That's pretty much all there is to this boss. She is quiet easy to beat and shouldn't cause problems as long as you remember to block the water jets.