It is really impressive that he became able to invoke dungeons so that he could constantly try new ones in the hope that he could find that potion.
Somehow, he tapped into whatever mystical mechanism that creates dungeons, something that I thought would be "simple" by how people treat dungeons here, but it clearly is something beyond normal understanding.
Maybe his current madness may even be caused by that connection... it certainly mirrors any dungeon game diver that gets insane grinding for that one piece of gear with the "god roll".