The Worn Keycard in Arknights: Endfield looks like a small flavor item, but it is tied to a specific hidden gate in Aburrey Quarry. If you picked it up early and then forgot what it does, it is very easy to lose track of both the vendor and the locked door it opens.
What the Worn Keycard is
The Worn Keycard is a 5★ Mission Item. It sits in your mission inventory rather than your normal consumables, and it is not consumed in combat or crafting.
Its only role is to unlock one abandoned area in Aburrey Quarry’s Listening Post. Behind that gate, you find gatherable materials and a single Aurylene, so it is mostly relevant if you are pushing exploration completion or hunting Aurylene.
How to get the Worn Keycard in Aburrey Quarry
The Worn Keycard is purchased, not looted, and the game does not strongly highlight it, which is why many players walk past it the first time.
Once purchased, the Worn Keycard is added permanently to your Mission Items tab. There is no additional quest step required to activate it; you can immediately use it at the correct door in the Listening Post when you reach that area.
Where the Worn Keycard door is in the Listening Post
The keycard is used in the quarry’s Listening Post section, on the 2B level. The door is tucked behind a short puzzle sequence, which makes it easy to forget or miss if you are focused on the main mission.
Interacting with the gate while the Worn Keycard is in your Mission Items will unlock the door and open the abandoned section behind it.
What you get for using the Worn Keycard
Opening the Worn Keycard gate does not lead to a cluster of treasure chests. Instead, the reward is lighter but still important for full completion.
- Aurylene: The key reward is one Aurylene located in this sealed Listening Post area. This counts toward Aburrey Quarry’s Aurylene total and is required if you are tracking down every instance of this collectible.
- Gatherables: The area also contains some regular gatherable resources scattered around the environment, similar to other abandoned corners of the quarry.
There are no additional missions, cutscenes, or unique gear tied to the keycard. Once you have collected the Aurylene and swept the room for materials, the Worn Keycard’s practical role is effectively complete.
Why the Worn Keycard is easy to miss
The Worn Keycard sits in the overlap between several systems in Aburrey Quarry: power routing, internal staff areas, and deeper Listening Post levels. You are asked to revisit the quarry multiple times for main and side missions, which makes it very easy to see the locked door early, forget where it was, and only later pick up the keycard from Lonnard.
It also does not show up as a standard quest marker with a dedicated mission, so unless you keep notes or map pins, you can easily end up with a key and no clear memory of the corresponding gate, or the other way around.
Quick recap
| Detail | Answer |
|---|---|
| Item name | Worn Keycard |
| Item type | Mission Item (5★) |
| Where to buy | Staff Lounge in Aburrey Quarry, from Lonnard |
| Cost | 100 Stock Bills |
| Where to use | Locked gate on Listening Post 2B floor in Aburrey Quarry |
| Access requirement | Clear the numbered generator energy gate puzzle, then take the side elevator down |
| Main reward | One Aurylene and some gatherables in an abandoned area |
Once you know both the Staff Lounge vendor and the Listening Post door, the Worn Keycard becomes a straightforward cleanup task: buy it from Lonnard, ride the elevator down past the generator puzzle, and claim the Aurylene waiting behind the gate.
