Update: after a little research online. it has been found that the "Mustachioed" in the caretakers name refers to a level designer for World Of Warcraft.
"Another Reddit thread details how a player found and entered the "Quality Well," whose wretched inhabitants were all named after Diablo 3's quality assurance testers. Yeah, that'll teach them for letting so much unquality pass their supposedly competent hands. Is that not enough literal Blizzard-bashing for you? There's evidence of a mustachioed WoW level designer roaming Diablo 3 as well. So what are you waiting for? Complaining on forums has done nothing. It's time to whale on the developers and hope they learn something from this."
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