During your journey in Crimson Desert, you will come across a variety of key objects and items that will be used to progress through the main story quests. One such item is the Mystical Key, obtained after you finish the previous quest, the Heart Beyond Borders.
This particular key can be used to open a specific door, which is way more convoluted than it should be. If you’re wondering how to complete the quest, you’ve come to the right place.
Examining The Engraved Key
Once you have the Engraved Key in your possession, make your way to the Inventory (Pause > Inventory menu) and select the key. Select the key using X and press A to begin the examination process.
Doing so will bring the key up in a first person angle. Hold down LB to examine and unlock the next portion of the quest, which has you head to Hernand Castle.
Making Your Way To The Castle
Unfortunately, the castle bars entry to those without proper attire. For this you’ll need a change of clothes. Make sure to have completed the ‘Actions Speaker Louder than Words’ game quest for this.
To begin, make your way to the distressed couple at Murkroot Ranch. After a brief cutscene, you’ll want to pick up the broom and begin climbing up the house, toward the chimney.
Aim using LB to clean the chimney using the broom, and you should be rewarded with the Hernandian Attire for your help. Equip it, and make your way to the gates once more.
The guards should now allow you to pass through (mostly) unrestricted. Go past the two gates and enter the Castle Hernand, making your way to the second floor via the door on your right.
Finding The Correct Door To The Alchemist’s Chamber
Once you’re in the castle, you’ll want to pick the right door which unlocks with the key. Unfortunately, Crimson Desert does not tell you this beforehand, making the whole process a bit of a trial and error.
Lucky for you, we’ve already completed this bit. The correct door is the one on your immediate left while within the room. The door should automatically unlock here, consuming the key in the process.
Once in the room, head to the shining gap in the wall and press X to interact with it and head to the next part of the quest.
