Diablo/Black Mushroom

This is the most intricate side quest in the game. Once arrived in the caves, at level 9, you may find an item that looks like a book, called a Fungal Tome, apparently without a use. Go to Tristram and take it to Andria. She will say something about an ancient magic and that, in order to make use of the tome, she will need a black mushroom.

Return to the labyrinth. Also in level 9, you should find a patch of mushrooms. Examine it to get the black mushroom (if you haven't brought the Fungal Tome to Andria yet, you can't do anything) and bring it to the witch. She will tell you that Pepin the healer is working on and elixir and that he needs the brain of a demon to complete it. Andria will then ask you to get him the brain and then bring her a bottle of the elixir he prepared.

Go back to the labyrinth and kill any enemy. You will automatically get the Brain. Collect it and bring it to Pepin. He will tell you that he was able to complete the elixir even without it and will deliver it to you, to take it to the witch. However, when you bring the elixir to Andria, she will tell you that she no longer needs it and that you can keep it. Drink it to increase your parameters.

REWARD: Spectral Elixir (+3 to all attributes permanently)