Ruined King: How to Get Illaoi’s Legendary “Heart of the goddess”

You have to unlock the Arcane forge by upgrading the “CRIMSON AMULET” you got in the main quest to the max level.

To do that, go back to “the drawned port”

And go to point A

If you have progressed enough in the main story, an npc will do it automatically

Then go back to “LIBRARY OF AGONY”, take the north path, and you can now open the door
Proceed to read every single books against the walls, it will trigger mini cutscenes and give you all legendaries quests.

To aquire the essence, you need first to go to the purification temple.
More precisely in the hall of radiance.

The item is on Point A, but it’s locked untill you put two rays on the two green crosses.
To do so, take the solar core (1) and put it on the receptacle point B, press the button right next to it.
it will open the acces to the second core (2)
take it and put it on the 1st receptacle (1), follow the light and point it in the direction of the green cross.
then go back to point B and press the button again, as previously follow the light and put it in the right direction

You got now the “raw” item, you need to “upgrade” it for the legendary

Go now to “THE WELL OF THE MOTHER SERPENT”
Point C, and drop the serpent in the pit

Complete the graveyard, it’s in the ending chest (point A)

If you cant open the gate, you have to complete the statue first (POINT B). Gather its parts and interact with it.

Complete the quest : “DEMONS OF MIST” (kill 3 elites mobs)
this quest become available once you’ve completed “HUNTING THE MIST” (same but weaker)

Both are given by Phillias (Point A)

You may have to reload the map once you finished the first one, cause the npc is kinda grumpy