During the Tilting the Balance mission in Assassin’s Creed Valhalla, you need to locate King Burgred’s hideout and defeat him. King Burgred’s hideout is located in a crypt near the confluence of the Arwy and Alne rivers. Locating the entrance to the crypt is quite difficult.
To reach the hideout, keep following the objective marker on the screen until it disappears. Once it disappears, you need to use your Raven to get the exact location of the hideout. It is a heavily fortified place with a church in the center. If you use Odin sight, you will notice that the objective location shows below the ground.
To find King Burgred, you need to find a way to the basement. The entrance is located in the left part of the base, near a red camp and bonfire. You will see a small house, but it is actually the entrance to the basement. Head inside and you will find a staircase leading down.
Follow the staircase and you will reach a room. Towards the right, you will see a small hole in the bottom of the wall with a crate place just in front of it. Destroy the crate and simply keep walking towards the hole. Eivor will automatically slide in through the hole and enter the adjacent room.
Kill the guards and keep proceeding down using the stairs. You will reach another room with guards, and there is a breakable wall right behind one of the guards. You can use oil jars nearby to break the wall and get the Fyrd Spear from underneath the water. Head back to the room and proceed to one right beside it.
Defeat the Skirmisher in this room and loot his body to get a key. Use the key to open the door to the next room where King Burgred is. A short cutscene will play and the fight with King Burgred will start. Defeating him is a bit tricky since you will be unarmed while he will be using his sword.
Your primary focus should be on parrying while fighting him. Since he has a shield as well, trying to attack first is not a good option. Wait for him to attack, parry, and try to get behind him and land a few hits. It might take some time to defeat him if your melee damage isn’t much, but if you are getting your parries right it shouldn’t be that hard. Once he is defeated, simply pick him and regroup with your allies.