According to aq wiki it is dropped by any monster in the entire game
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The Crossroads are the place where you battle 2-16 monsters depending on your level and you might get a rare treasure chest or a different treasure chest containing gold.
No, there is not a chest in "Crossroads".-King 1658
The easiest place to get it would be the "Battle Monsters" button. I had a Adventurer LvL11 and kept clicking "Battle Monsters" to train and found the Rare Treasure Chest. Yet I have not seemed to have gotten it on my LvL54 X-Guardian yet.
to get to a rare chest, you go any where it has battles. the way i got my blade of awe was that i clicked battle monsters. but the point is is that it is rare so your not going to find it that easily. hint: when you get the blade of awe go to that Victoria girl by the shop and hit visit privatly. after that click awe weapons and change it permantly it only cost 20 gold or tokens. and you have the blade of awe im pretty sure you need 4 parts of the weapon 1. the handle 2. the part above the handle 3. the blade 4. the runes
You get it on Halloween. another person btw, its rare now (2012)