In this walkthrough guide, we’ll explore how you can complete the ‘A Long Lost Key’ quest in Assassin’s Creed Shadows.

The ‘A Long Lost Key’ quest in Assassin’s Creed Shadows is one of the major quests that you’ll have to complete when you play through the game’s new Claws of Awaji DLC. Just preceding this one is the Way of the Bo quest, where you’ll meet the Bo master. At the end of that quest, he’ll task you with finding Tsuyu’s key.
However, he won’t mention the exact location, instead giving you certain clues. This can make hunting down Tsuyu’s Key challenging for first-time players. So, in the following guide, we’ll explore how you can find the key and go on to complete the A Long Lost Key mission.
Where To Find Tsuyu’s Key During A Long Lost Key Quest in Assassin’s Creed Shadows

As we said, after completing the Way of the Bo quest during Claws of Awaji, you can straightaway jump into locating Tsuyu’s Key. Although you don’t have an exact location where it could be, you have three clues thanks to the Bo Master. These clues are as follows:
- The Key is west of the Yura region.
- It’s buried close to the Okunoion Sasayama Shrine.
- You can reach the key’s location through the Mountainside Ruins.
So, following these clues, your first order of business is to make your way to the Yura region of the Awaji Island map. It’s in the southern portion of the island. From there, start heading west toward the Okunoion Sasayama Shrine viewpoint.
This one is just to the north of the Mountainside Ruins. Once you reach this spot, you can look around to find the key. If you’re in the correct spot, you’ll be able to dig the key out. Refer to the image above for the exact location.
How To Complete A Long Lost Key Quest
As soon as you find the key, a cutscene triggers. It’ll show a swarm of enemies ambushing you, including the mysterious opponent known only as “Unknown.” You’ll have to fight and eliminate all of the standard enemies during this ambush attack. Keep in mind that the Unknown will attack you from a distance. You need to carefully dodge all of his long-range strikes. The Bo weapon can be highly effective in this scenario, allowing you to easily deal with the close-range enemies before you can go after the Unknown.
Once you’ve dealt with the standard opponents, make your way toward the Unknown. However, unfortunately, you won’t be able to catch up with him, as he’ll flee the battlefield. This concludes the A Long Lost Key quest while also ushering in the start of The Regalia quest.
![AC Shadows logo [Source: Ubisoft]](https://static.deltiasgaming.com/2025/03/AC_Shadows_Fan_Kit_Wallpapers_Horizontal-Faceoff.avif)
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