Elden Ring Shadow of the Erdtree

“In the lightless depths lies the grave of an ancient civilization. It is here Mohg, the Lord of Blood, is building his palace, to be the seat of his coming dynasty named Mohgwyn. And whatever nightmares that may bring.”

Background: The ambitious demigod stole Miquella, brother of Malenia, from the Haligtree while the cursed youth was in pupal form, with the goal of raising Miquella to become a god and elevating himself to consort in the process. As his name suggests, Mohg wields bloodflame magic and can perform a powerful ritual that causes major damage to the player while also regaining his health.

Location: Mohg is found at the end of Mohgwyn Palace. The quickest way to reach this is by completing White Mask Varré’s questline and using the Pureblood Knight's Medal he gifts you.
 

Mohg, Lord of Blood battle tips:

• To give yourself a big advantage in the first half of this two-phase fight, find Mohg’s Shackle (found in the Subterranean Shunning-Grounds under Leyndell) and use it up to two times to temporarily restrict Mohg’s movement.
• Create a mix containing Purifying Crystal Tear for your Flask of Wondrous Physick and drink it as Mohg transitions into the second phase to prevent almost certain death from his devastating attacks.
• As blood loss is almost inevitable, equip the Talisman Lord of Blood's Exultation, earned by defeating Esgar, Priest of Blood in Leyndell Catacombs, to gain an  attack power boost when you hemorrhage.

When Mohg is defeated, resting at a Site of Grace will cause a new character called Leda to appear in front of Miquella’s cocoon. While you do not need to converse with her, Leda’s appearance indicates that you can now touch Miquella’s arm and begin exploring the expansive Realm of Shadow.