This page of the Resident Evil Village guide explains where to find and how to combine the Silver Ring and Azure Eye treasures. These are the first combinables that you can find in Castle Dimitrescu.
- The game does not allow you to return to Castle Dimitresu after you leave it. Try to find both items before continuing your journey.
- Don't sell the Silver Ring or the Azure Eye treasures alone to the Duke. By combining both treasures, you can create an artifact of a much better quality. As a reminder, the game allows you to combine treasures marked as Combinable. You can select one of them and select Combine. Combine the Silver Ring with the Azure Eye after you have found both treasures. You will gain the much more valuable Azure Ring.
You can find the Silver Ring in the Hall of Pleasure, the same room where the Mask of Pleasure key item is located.
The Hall of Pleasure is initially closed. To open it, you need Dimitrescu's Key, which you can find on a candlestick in Dimitrescu's Chambers. Getting this key is a crucial part of advancing in the campaign.
In the Hall of Pleasure, have a look inside the desk drawer to find the ring.
Getting the Azure Eye is much more complicated. You have to obtain the Iron Insignia Key first. You receive it as a reward for solving the piano puzzle in the Opera Hall, as a part of the main campaign.
Once you've obtained the key, you must return to the Dungeon you visited earlier. The place where you can use it is shown in the image above.
The dungeon is on level B1 and you can get there from the Kitchen adjacent to the main lobby. Expect encounters with singular monsters along the way. You must use the Iron Insignia Key to open the gate in the northeast corner of the dungeon.
In the new room, there is a Crumbling Wall (marked with an icon on the map). It is shown in the picture and you must use the Pipe Bomb to destroy it.
Tearing down the wall will allow you to reach the loot, but more importantly, you can now light up one of the braziers that hang from the chains. To do so, you need to swing it towards the hole in the wall.
That's not all - you need to light the second brazier as well. Both objects are quite far away from one another and unfortunately stop swinging quite soon. The solution here is to fire your gun at an inactive brazier and quickly push the already burning one towards it. The desired end result is shown in the picture above - both braziers must be burning.
You can now examine the sarcophagus. Inside, you will find the Azure Eye treasure.
As a reminder, you must combine both items (Silver Ring and Azure Eye) in the Treasure tab of your inventory to create the much more valuable Azure Ring.