I believe you need to clear two of the dungeons where the door had been locked. One is in the mine, one is in the forest ruins (secret room in the library), one in the volcano, and one in the ice area near the bridge you can repair. Once you have the parts you can make an item at your cauldron. All I have to say is the puzzles can get very annoying. So annoying that the dev placed cheats that cost mana to use.Someone can tell me where I can find the key? I am stuck in the main quest View attachment 5480238