Whether you find the key legitimately through exploration or use a community-shared, safe, and legitimate mod, the experience of discovering the secret room is a highlight of Act 3. Final Thoughts on Runic Key Acquisition

The Runic Key is a unique, non-consumable item that acts as a key to a locked chest found within the "Notch’s Mine" secret level in Act 3. While many keys in the game are used for generic locked chests, the Runic Key is specialized.