If you pay attention while you fight the various enemies across the world, there are two versions of the Crucible Knights. There are those who wield the sword and shield and others that wield spears. The spear-wielding knights have a different armor than their sword and shield brethren. Here is how you get the Crucible Tree armor set in Elden Ring.
To obtain the Crucible Tree armor set, you first need to make your way to Deeproot Depths. This is done by defeating the gargoyle boss in Nokron, Eternal City. Once the boss is defeated, rest in the coffin in the back of the arena near the waterfall. This will initiate a cutscene that takes you to Deeproot Depths.
Once you reach Deeproot Depths, make your way across the large gap using the tree roots. Go through the area to the northwestern corner. Here, you will find a large tree stump that you can go inside. The tree stump is guarded by a Crucible Knight boss. You can either fight the boss or get around them using your horse. Open the chest inside the tree stump to obtain the armor set.
Read more on gamepur.com