Free Yoruba!

Hint: Where is Yoruba's cell?

Hint: How do I get to Yoruba's cell?

Hint: I can't find the necklace.

Hint: What do I do with the necklace?

Hint: Can I use the revolver to shoot Melkior?

Hint: Why can't I go back the way I came in and look for Melkior's diary?

Hint: How do I get out of here?!