Ketheric Thorm is a powerful enemy in Baldur’s Gate 3, and defeating him can be a difficult task. Fortunately, there are some strategies that can help you defeat him. Here are some tips for taking down this formidable foe:

1. Use Crowd Control: Ketheric Thorm has a wide range of powerful abilities, and it can be difficult to take him down if you don’t have enough crowd control to keep him at bay. Use spells such as Hold Person or Web to keep him from attacking your party, and then focus your attacks on him.

2. Use Dispel Magic: Ketheric Thorm has a variety of magical abilities, including powerful buffs that can make him even more dangerous. Use Dispel Magic to remove these buffs and make him more vulnerable to your attacks.

3. Focus Fire: Ketheric Thorm is a powerful enemy, and it’s important to focus all of your attacks on him. Have your party members focus their attacks on Ketheric Thorm, and use crowd control to keep him from attacking your party.

4. Use Damage Over Time Effects: Ketheric Thorm has a lot of hit points, so it’s important to use damage over time effects such as poison or disease to whittle away his health.

5. Use Buffs: Ketheric Thorm is a powerful enemy, so it’s important to buff your party before engaging him. Use spells such as Bull’s Strength or Shield of Faith to increase your party’s damage output and survivability.

By following these strategies, you should be able to defeat Ketheric Thorm in Baldur’s Gate 3. Good luck!