Defeat the risen corpses and try to catch the lonely soul. In the second area kill the enemies and go south to an Essence of Cunning . At the east end is where you will find the Lonely Soul. Intimidate or fight it, which is actually a Hunger Demon in disguise, then grab the Essence of Magic. Open the coffin on the right side to reveal an Essence of Constitution . Leave the Shadowy Crypt and return to the Blackmarsh Undying via the south exit (where you grabbed the Essence of Cunning).