Go Upstairs to the Pyrilen area. its the smaller circle room South East of the most north room on the map.
If you use Brewall's map, same room as Familiar Venomtail.
as someone has said, "Down the stairs from the statue, first left, past a junction, down again to a room with a table, a couple of Chimeras and a couple Pyrilens. Craftmaster spawns on your left."
I didn't know where the statue was. Its right before the King/Queen area.