I'm just pondering "two hard things" (Shakespeare quote, if anyone's counting). The first is, how did Gman smuggle that mirror into the oubliette? The second, and more important, is, how the heck did the oubliette get over here? In the dank, dark, dangerous space beside the moat - oh, yes, that's exactly where I'd expect it. Hearing echos from it in the halls of the castle, sure, that happens. But here, in the sun-splashed, verdant fields of the Green Club? Even for the kingdom, it makes no sense.
But Gman can clean all that broken glass up by himself. I ain't goin' anywhere near him if he's playing with sharp objects!