Usage of a certain key

[Bonkers]

I've been playing through the game severyl times now and noticed one thing. After killing the first Dai Pao, inside the spider caves, there is a dead body with two antidotes next to him, holding a key. My problem is that I've never found the chest or door this key belongs to.

Does anyone of you know where this key is used?

[Umbral Skorpa]

bit late for a reply, but if it is the one i am thinking of, the dead orc lying in the stream,
then the key is to a chest inside the temple. the part where you first go in before the goblins close the gate in front of you, there is a large room with a pillar that you can break down, and a statue that you can break. the chest is underneath a rotten corpse, with a battle axe. there is also a note next to it explaining that someone locked it because of the goblins nearby.

[Bonkers]

It certainly is a bit late, but thank you for the clarification. Since I always pick the key up and the chest is so far away from it, I never really made the connection.