Baldur’s Gate 3: Decipher the ancient book – How to find and open the necromancy of Thay

Baldurs Gate 3 Nekromantenbuch öffnen Titel

To decipher the ancient book of necromancy from Thay in Baldur’s Gate 3, you must overcome several challenges. MeinMMO reveals how to unlock the necromancer’s book from Thay – without getting lost – right above with a quick guide, below in detail.

Update from 01.09.2026: We have reviewed the article and slightly adjusted the structure.

Finding and opening Necromancy from Thay – Quick Guide:

  • Enter the apothecary in the destroyed village in Act 1 and find the secret basement door.
  • Upon arriving in the basement: Look for the rusty key and the next secret room.
  • Outsmart the talking magical mirror and disable the traps.
  • Find the Dark Amethyst in the nest of the phase spider beneath the Destroyed Village to unseal the ancient book of necromancy from Thay.

Step 1: Quest Search the Basement – How to find the necromancer’s book from Thay

What should I do? Go to the Destroyed Village to the second building on the left side – the Apothecary. On a counter lies a book with the quest “Search the Basement”.

Behind this counter, you will find the hatch to the underground adventure. Upon arriving in the basement, you will find a rusty key on a shelf in the westernmost room of the laboratory, which you need.

Behind three wooden boxes next to the large cupboard, you will find a lever to the next secret room after a perception check. You can lift and move the boxes to reach the lever. Afterwards, the cupboard moves, and the passage is open.

Outsmarting the magical mirror

You will encounter some enemies. Once you defeat them all, you will come across an ornate mirror. Start a conversation with the talking magical mirror and outsmart it with the following sequence of answers:

  • Yes, an ally! An ally of your master.
  • Szass Tam is evil and vile.
  • Balm is used for wound cleaning.
  • I would look for a spell that frees me from this worm.

After that, the magical mirror lets you through, and you enter a room.

In the middle of the room, you will find a research note on the table that continues your quest. Then open the closed gate with the rusty key. Behind the closed gate, you will find the necromancer’s book from Thay.

Be careful! It’s best to disarm the traps beforehand – there are many. And then grab the book.

Here are tips for all classes directly from the developers:

Start video
Baldur’s Gate 3: Developers give 30 minutes of tips on all classes

Step 2: Decipher the ancient book

How to open the necromancy from Thay

To follow the dark path of necromancy and open the book, you need an item called Dark Amethyst. Visit the Destroyed Village, this time not a house – but The Whispering Depths:

  • Go to the well in the destroyed village, investigate it, and enter the whispering depths.
  • Be prepared for a battle against nasty phase spiders.
  • Make your way to the nest of the phase spider matriarch – all the way in the west.
  • Approach stealthily (Tip: invisibility potion), or defeat the matriarch.
  • The glowing purple Dark Amethyst is under her nest next to a broken pillar – press “Left-Alt”.

To indulge in necromancy or to destroy the ancient book?

After you have collected the amethyst, you can read and open the necromancer’s book again. However, there are multiple ways to utilize the necromancy from Thay.

Here are the options:

  • Read it yourself (successful): Discover the secret of the necromancy from Thay yourself. When flipping through, you must face a total of three wisdom checks with increasing difficulty – 10, 15, and 20. If you succeed, you will receive the achievement “Hidden Knowledge”: A bonus of +1 on all Wisdom saving throws and skill checks. You will also receive the spell: “Speak with Dead” – a 3rd level necromancy spell. However, you cannot read the last page yet. The quest will thus continue, which is quite a lengthy process. If you want to know how to read the last page – then scroll down. Warning: Spoiler alert!
  • Read it yourself (unsuccessful): If you fail the wisdom checks, you will be cursed depending on the number of failed saving throws (After the first fail with “Whispers of Madness”, after the second fail with “Unholy Knowledge”). However, both curses can be lifted with the spell “Remove Curse”.
  • TIP: Class options: Some classes can adjust the difficulty of the roll or change the conditions:
    • Bards can roll Performance Checks (DC: 5, 10, 15)
    • Wizards can roll Charisma Checks (DC: 5, 10, 15)
    • Warlocks can make their first roll as a Charisma Check with a difficulty of 5. For the others pages, it’s the prescribed Wisdom Checks.
    • Sorcerers can make their first roll as an Intelligence Check with a difficulty of 5. For the other pages, it’s the prescribed Wisdom Checks.
    • Clerics with deities aligned with the Dark/Evil (like Talos, Gruumsh, or Lolth) receive a Wisdom Check with a reduced difficulty of 10 instead of 20 for the third page. Shadowheart, as a cleric of Shar, also qualifies.
  • Gale: You can give the necromancy from Thay to Gale to help him. You will not have this option if you open the book beforehand.
  • Astarion: After opening, you can give the necromancy from Thay to Astarion. This earns you his approval and advances his unique story. However, you can only give the book to one of the two story characters. It might even lead to a closer romance with one of the companions.
  • Destroy it: You can destroy the necromancy from Thay with holy damage – which I would not recommend. For example, you can cast “Guiding Bolt” on the book with Shadowheart. But then three dangerous shadow enemies await you that are very resilient. Without a strong party, you will likely die very quickly. Astarion will not like the destruction of the book, but Karlach, Lae’zel, and Wyll will be grateful.
  • Put the book away: Leave your decision open for now and make a choice later in the game.

Warning: Spoiler! From here on, the article contains information that reveals itself much later in the game.

Step 3: Reading the last page of the necromancer’s book

How do I read the last page of the necromancy from Thay? To learn the complete secret of the necromancer’s book from Thay, you must first arrive in Baldur’s Gate. There, you belong to the place “Charming Little Things” – which is part of the quest line “Wizards of Waterdeep” (Gale). Go there, look for the librarian’s office, and interact with the book that is clutched on the shelf. A dark portal will open, teleporting you to a spell vault.

Another way to reach this spell vault is to press one of the large buttons in Lorroakan’s tower, which is labeled “Treasure Room”.

Explore the entire area of the spell vault. Once you are in the riddle room, pass through the doors in the following order:

  • Silver Hand
  • Summoning
  • Wish

However, watch out for traps. Afterwards, you can use the lever in the last room and make your way back to the first room – the Elminster vault should be open.

Inside, you will find the Tharchiate Codex. You need it to read the last page of the necromancy from Thay. The wisdom check is not easy. You need to roll a 20. If you succeed, you will be richly rewarded: With the last page, you will receive a powerful spell that allows you to summon ghouls.

If you are still unsure whether you want to take Gale and Astarion into your group, we have a suitable guide for you. With it, you should be well equipped to form your dream team: Baldur’s Gate 3 Guide to the Companions – How to create the best group

This is an AI-powered translation. Some inaccuracies might exist.
Source(s):
  1. PCGamer