Ketheric Thorm is the final boss of Act 2 in Baldur’s Gate 3 and the commanding general of the army of the undead. Being a necromancer, Ketheric Thorm is both invulnerable and invincible. However, with the correct party members and Nightsong on your side, not everything is lost while fighting this one chosen by the god of death, Myrkul.
Ketheric, Orin, and Gortash have joined their powers to fight against Baldur’s Gate by controlling the Elder’s brain. You must fight Ketheric Thorm and his companions to stop them from laying waste to Farun. In this guide, we will let you know how you can achieve this impossible feat easily.
Ketheric Thorm location in BG3
Ketheric Thorm can be found at the top of Moonrise Tower in the Shadow Cursed lands. Before heading towards Ketheric Towers, you must complete the following quests.
These quests include going to the Gauntlet of Shar, collecting all the Umbral Gems, and finally saving Nightsong from dying. Otherwise, she will either be killed by Shadowheart or Balthazar.
Saving Nightsong is of utmost importance because she will help you in the battle against Ketheric Thorm in BG3. She is also why Ketheric becomes vulnerable to attacks instead of being immune to all attacks.
When you reach the door of the moonrise tower, you will come across Jaheira. You will need to ask her to join your team. She will tell you that she is committed to her people. If you insist, Jaheira will agree to fight alongside you.
Now, go through the door, and you will reach the top of the Moonrise Tower in Baldur’s Gate 3. Ketheric Thorm will be standing on a platform where the dialogue sequence will start.
Ketheric Thorm Dialogue options
When you approach Ketheric Thorm in BG3, there will be a few dialogue options. The first three will trigger him to get angry. At this, Nightsong will swoop in from above and throw him down. She is angry at what Ketheric Thorm has done to her and Isobel and wants to take his life. This will then start the battle against Ketheric.
You can also roll a persuasion or intimidation check and ask him to surrender. This will make him ponder, but Nightsong will come from above, and the fight will continue. This will prove valuable later in the fight.
How to defeat Ketheric Thorm in BG3
The fight with Ketheric has three phases, depending on your dialogue choice. The first phase will occur on the rooftop. The next two phases will be in the Mind Flayer colony.
After you have ended the dialogue with Ketheric Thorm, the fight will start. If you have Nightsong with you, she will significantly damage him. The arena will have four Necromites on each side.
There will also be a mage called Susdera. She will be very annoying and needs to be dealt with first. Finally, there will be an undead dog called Squire in BG3, which is relatively slow and not a big problem.
Phase 1
First, deal with the Necromites on the left and right. You can do this by using Ice Storm or any other AoE attack. They don’t have much health, and the Ice storm will also slow Ketheric’s undead dog, Squire, in BG3.
Next, you need to take care of Susdera. She will attack you with many damaging spells, such as Fireballs, which can damage your whole group. Susdera will also spawn more Necromites by placing eggs, which incubate and then release them. In the first phase, she is more dangerous than Ketheric or any other enemy. Destroy the eggs before they hatch.
You can take on Ketheric Thorm in Baldur’s Gate 3 when all the above are defeated. During the fight against the minions, Ketheric will periodically come down from his balcony and hit you. He has melee-based attacks and a small amount of HP. When Ketheric’s health drops to about 30 percent, a cutscene will play where Nightsong flies up, and Ketheric will summon his tentacle from one of the towers.
This tentacle will knock down Nightsong and take her with it. Ketheric will also flee the scene. Now, you must follow him down to the Mind Flayers colony through the Oubliette.
Locate Ketheric Thorm in the Mind Flayer colony
Once you jump down, you must move towards the southwestern part of the colony indicated by the circle. This place is littered with Mind Flayers, so move with precaution. When you reach a lift-like area, interact with the blue strings to the right of the lift to go down. This will take you to a small corridor with a large door. As you approach it and open it, a cutscene will start.
You will find Ketheric Thorm, Orin, and Gortach, with Duke Ravenguard as a hostage here. Ketheric, Orin, and Gortash will discuss an army marching towards Baldur’s Gate.
Phase 2
After Gortash and Orin’s conversation, they leave, and you can interact with your characters. You must position your characters to deal the most damage because the fight against Ketheric Thorm will be tough in BG3.
Now, start by moving your ranged attacker towards the left platform of the arena. This character will also take care of the Necromites here. Look around the arena to find Nightsong in restrains. You must send one of your ranged or melee characters to help free Nightsong.
She is also important because she will make Ketheric Thorm vulnerable to attacks in BG3. To move around undetected, use either Misty Step, Dimension Door, or Teleportation Arrow to reach Nightsong. Select “Free Nightsong” action to make her fight alongside you.
Finally, you must move one character before Ketheric Thorm to start the next cutscene. After he has delivered his speech, you can choose the persuasion or intimidation dialogue option and make him surrender. If you succeed with the persuasion roll, the fight in the second phase will not go through, and another cutscene will start in which he jumps to reveal the final phase boss.
If you fail the persuasion or intimidation check, the Phase 2 fight against Ketheric Thorm and his lackeys will commence in BG3. First, start by helping out Nightsong, as she is the only one who can remove invulnerability from Ketheric Thorm and make him vulnerable to your attacks.
After this, take care of the intellect Devourer on the left platform. It doesn’t have much health and can easily be defeated. Next, take care of the Necromites on the right platform. After that, you can focus your attacks on Ketheric Thorm in BG3, who has about 30% of his total health remaining.
Ketheric will deal damage through melee hits and incubate eggs to gather more Necromites to fight alongside him. Deal with the eggs like before, and don’t let them hatch.
You will also find the Mind Flayer, which has a few high-intensity attacks to deal extra damage, and it is better to deal with all the minions before the final phase.
Phase 3
If you succeed with the persuasion check or defeat Ketheric Thorm by bringing his HP to 0, he will fall into the void in the platform. From inside the void, the Lord of the Bones, called Myrkul, will rise.
Ketheric Thorm, in his Myrkul form in BG3, uses melee attacks from his sickle and shoots ranged magic attacks simultaneously. He also sends out incubated eggs, which release Necromites. If you have defeated all the minions before, this battle will not be a big problem because Myrkul doesn’t move and only stays in one place.
You can deal with ranged magical damage from a safe distance and place a melee-based tank character like Lae’zel to handle the harsh blows. Murkul will, however, have the Bone chill aura around him. This aura blocks healing spells on the characters, so keep a close eye on your melee attacker.
If Ketheric Thorm consumes a Necromite in BG3, he will get the ability to use the Finger of Death spell. Finally, if you have Shadowheart in your team, you can pair her attacks with Nightsong to deal enormous damage and kill the beast without worry.
When Myrkul is dead, Ketheric will return, but he will fall and die instantly. You must reach Ketheric’s body and retrieve his netherstone from his chest. When you have the stone, the Dream Visitor will show up. They will tell you that the Netherstone is a way to control the Elder’s brain and the tentacles.
The Dream Visitor will tell you that there are three Netherstones, which are the key to controlling the crown worn by the Elder’s brain. They will further explain that Gortash is the chosen one by the God of Tyranny and Orin is the chosen one by the God of Murder in Baldur’s Gate 3. After the dream visitor goes away, you can loot Ketheric Thorm’s corpse in BG3.
Ketheric Throm rewards and loot
After the fight and the dialogue sequence, you can loot the body. You will get the following items.
- Ketheric’s Warhammer
- Ketheric’s Shield
- Reaper’s Embrace
Ketheric’s shield provides +2 armor class +1 on spell saves and attack rolls. You can also use this shield to deliver Shield Bash, which makes enemies prone.
Reaper’s Embrace will provide a +19 armor class. You will have increased protection from magical damage. It gives an advantage on Dexterity saving throws but without will. Gives a disadvantage on Stealth checks. You will get the cantrip Howl of the Dead.
Ketheric’s Warhammer deals 3 to 15 damage, +1 enhancement, and 1d4 psychic damage.
