This Elden Ring walkthrough will help you upgrade Castle Sol and collect a key item for Millicent’s questline and other loot. Castle Sol is located in the Giant’s Peaks region in Elden Ring. You’ll face Lion Guardians, Banished Knights, and then Commander Niall as the final boss of this Castle.

How to get to Castle Sol in Elden Ring

Castle Sol is located at the top right of Giant’s Peaks, which you can approach by traveling from Astronomer Ruins. You will be able to see Castle Sol from afar due to its large size.

The location of Castle Sol is shown on the map. You will be able to enter Castle Sol from its main gate.

Elden Ring Castle Walkthrough

Enter the castle through the main gate and two lion guardians will greet you. Take them out and loot them for Dark Smithing Stone, Old Fang, and Beast Blood. Move now above the platforms using the stairs.

As soon as you climb, a bird will watch you from above. Defeat the bird and the two wolves that roam the area. Go straight and go through the door. Inside the room will be a staircase that you can use to climb to the top.

Once outside, you will face three soldiers, and one will shoot arrows from afar. Bait the soldiers into the room you came from to be safe from arrows. Defeat them both and charge the third soldier with the crossbow.

But when you get to the stairs, a powerful knight will appear who will attack you. You can ignore the knight and enter the Eclipse Church just in front of the stairs.

Inside the church will be a site of grace on the left. Go back and go straight to the room in front of you. From there, turn left and continue straight. Inside the room, you will find three Albinaurics that will crawl towards you to attack you.

Defeat them and go upstairs. In the upper room will be a suspended Albinauric who will scream and spawn spectral knights if he sees you. Shoot him down before he screams so you can get through without having to deal with Spectral Knights.

Once outside, there will be an elevator to your left with a lever and Commander Niall Boss’s room with a yellow mist in front. Be sure to use the lever on the left to create a shortcut.

How to defeat Commander Niall in Castle Sol

Commander Niall can be a difficult boss to fight due to the Spectral Knights he spawns at the start. Since you’ll be facing three powerful enemies at once, make sure to spawn a powerful Spirit Ash on your side.

The Spirit Ash will keep the Spectral Knights busy while you deal with the boss on your own without any distractions. Also, make sure you have equipped a powerful weapon with high-stagger attacks.

One of the two spectral knights that will appear will be carrying a sword and a shield, while the other will be equipped with two swords. The Knight with Two Swords will be the more aggressive of the two enemies and will charge at you.

It is best to eliminate him before facing the other enemies. But, you will have to keep an eye on the boss to see if he is about to attack you or not.

The Spirit Ash can distract the boss from you, but it all depends on the positioning of your summon.

After defeating the two Spectral Knights, it’s time to face the boss one-on-one. But, as you defeat Niall’s allies, this will increase tremendously.

Commander Niall’s attacks deal Frostbite damage, which will continue to drain chunks of your health if you get hit by them.

One of his moves is to spin in a full circle and create a whirlwind of Frostbite over a large area. The boss will keep chasing you throughout the attack and will finish it with a swing of his staff.

He will also use electricity by sticking his staff into the ground and creating an electric shock wave in your direction. You can dodge this by rolling from one part of the arena to another until the attack is over.

Most of his attacks can be dodged by rolling the other way. When he dashes in a direction and starts charging towards you, dodge to the side and wait for the move to complete. This move will tire him out and you can use this opportunity to beat him to a pulp.

A few strong attacks will down Commander Niall in a second. Once defeated, you will get the Veteran Prosthesis (A key item needed for the Millicent questline) and 90,000 runes.