another tip i dont think i saw in here (but i only skimmed) is if you unequip your stuff before you enter the quest, your shadow will be naked, dealing less damage and with less defense. then when you enter the black room with the blue light, unequip again.
Some screenshots for an example/proof. double that and my fairly extensive buff up(look at all dem scrollz!!1!!eleven) i could have easily gotten away with using just stones or just pots.
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