Death Harnessed: Theories of Rathma is a Diablo 4 quest item. The item is required for a quest in Act 1 and is obtained by traveling to the Horadric Vault with Neyrelle. The necromantic runes on this charmed book, which belonged to the ancient dark wizards of Diablo 4, are visible. You must successfully finish the campaign quest Fledgling Scholar in Diablo 4 to receive Death Harnessed: Theories of Rathma. The Fledgling Scholar quest includes finding this book of black magic. Worry not, read below for how to finish Fledgling Scholar in Diablo 4 and obtain Death Harnessed: Theories of Rathm.
Fledgling Scholar Quest - How to Get Death Harnessed: Theories of Rathma in Diablo 4
The Fledgling Scholar quest needs you to locate Death Harnessed: Rathma Theories. Neyrelle is looking for a book that can transport you across the Black Lake to Lilith. When you enter the Horadric Vault, you'll be given the option to explore the area and unlock the main door. Another book in the room to the right will break the charm and allow Neyrelle to open the door.
Once inside, proceed up the left-hand corridor. Chat with Neyrelle at the fork with two locked doors to have her unlock the left door. Continue without her while she investigates the rooms you've already visited.
You’ll need to fight through a variety of demons and skeletons as you explore the hallways of the vault, so be prepared with potions. You’re looking for a healing fountain toward the northern part of the map, with a singular path leading away from it to the boss of the area.
How to defeat Tchort, Herald of Lilith
You must defeat Tchort, Herald of Lilith in order to obtain Diablo 4's Death Harnessed: Theories of Rathma. However, this boss may be more tough and powerful than you anticipate, so prepare to break a sweat. To beat Tchort, you must perform the following actions:
Avoid her projectile and melee assaults.
When she begins to deplete your health, move away from the area and avoid it.
Destroy the fire orbs she summons and make sure they don't burst. This may be useful because they occasionally drop health pots.
Once defeated, the whirlwind around the book will disappear. Go up to it and collect it to obtain Death Harnessed: Theories of Rathma. Return the spellbook to Neyrelle to complete this part of the quest.
Death Harnessed: Theories of Rathma Bug
This glitch causes Death Harnessed: Theories of Rathma and the Holy Chalice to appear at the Kyovashad fast travel point. Even after finishing the quests linked to them, these two items continue to spawn at the waypoint.
Players who were afflicted by this problem were also unable to advance past the 34/35 quest mark in the area, and there does not appear to be a fix that players could use to solve the bug for themselves.