Gein is interested in an old legend recorded in the Historibus Compendium, a book kept in the Xelorium Museum. So he's asked you to go and learn a bit more about the legend, and verify if it really tells of a box with terrible power...
This fight must be done alone. You must defeat The Devourer of Books. It uses some powerful long-range spells, but needs a line-of-sight to hit you. It also has minimum range, meaning that it can't attack you if you are too close to it. You could try to hide behind walls to avoid its attacks until it gets close, then run near it and keep it close by locking it or reducing its MP. Alternatively you could just use very long-range spells and stay very far away from it, either way don't fight it recklessly and be ready for a challenge.
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→ You must go to 4 different maps and win 4 different fights. The maps are [2,5] in the Gonebyways, [4,2] in the Present Day, [3,-4] in the Uncertain Future and [6,-4] in the Uncertain Future. At [2,5] you must defeat a Time Huntress, who fights like a Kartridge. At [4,2] you must defeat a Time Hunter, who fights like a Cra. At [3,-4] you must defeat a Time Huntress, who fights like an Eniripsa. At [6,-4] you must defeat a Time Hunter, who fights like a Kanazure. These fights must be done alone, and can be hard if you're not prepared, so be ready for a challenge. Don't fight them recklessly and try to keep yourself safe with defensive spells. The one that fights like a Kanazure is particularly dangerous.
Find the map: Methea's Stone room
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→ Go to [7,3] (in Xelorium) and talk to Hyperia Shrik. You don't need a key to enter the Megalith for this quest. Once inside the Megalith, walk onto the Roman Numeral tile that corresponds with the current in-game hour. For example, if the current in-game hour is 03:00 or 15:00 you would step on the III tile. You can use the /time command to see what the current in-game time and date is.