Yes it is possible, you need to figure out how to get to the Golden Key. I know a half way, you need all corpses to put on all graves in the rookgard, so you can use a cup of blood(gotten from empty cup, usable on dead rat's blood), and to reach the Golden Key. Second, you need to pull the lever floor up of NPC Tom in rookgard(west of academy). The lever can be seen under the bucket. Doors are locked, but you need to figure out how to open it QUESTION:'???' Pushing that lever is unlocking a doors for Ghoul.
-Reaching the Ghoul is the point of a life ring, which can be changed for Golden Key in NPC '???'.
-Unlocking key for minotaur mage room is from Golden Key '6???'
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