Brighstone Key is a key item in Dark Souls 2.
- Leads to a chest containing a Fire Seed, Great Fireball and the Black Knight Ultra Greatsword in the room where spiders fall from the ceiling (on the way to The Duke's Dear Freja boss fight).
- When opening the door to the room that contains the chest, it will trigger a spider to spawn. Again when entering the room containing the chest, approx. six spiders will spawn in the previous room.
- Obtained as a drop from Duke Tseldora after killing him in the Lord's Private Chamber. (Note: If you kill him and do not pick up the items, you can use a bonfire ascetic on the "Lower Brightstone Cove" bonfire to fight the Duke's dear freja again, and there he will be).