The Tree of the Knowledge of Good and Evil

You get this achievement in the 'One Night in the Woods' DLC/chapter of the game. It is unmissable as it is part of the story line. Solution to get this below. Credit goes to the Walkthroughking (). The below is right after you cross the bridge. In this section you can get the following three achievements out of the way:
- Italian Sidejob -- see below, but also see Hellgate Aeon solution:
- Demonology
- A Deal with the Devil

Note: Italian Sidejob is missable if not done correctly on first attempt
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Use the fire and you will pick up a flaming torch. Pick up the large bucket, then go to the right. Use your candle on the moon to collect the moonlight. Now climb up the stairs to the top of the waterfall. Pick up the two stones blocking the flow of water, and place them on either side of the flow out the bottom - this will divert all water to the side passage. There is an achievement for doing this perfectly on the first attempt Italian Sidejob.

Use your flaming torch on the vines. Look at the symbols beneath each of the demons here. Pick up the dagger and collect water in your bucket, then return to the left. Put fire in the left chalice and water in the second chalice. Use the dagger on the third chalice, and the moonlight on the final chalice Demonology.

Place Harry's hair into the waiting hands of the final demon, then use your candle on the portal A Deal with the Devil.
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