Seriously? I peak in on his cave every now and then and he's never ever there. My server isn't even populated and I go there when it's the dead of morning, and there's never a Pianus on any channel. You'd think after Big Bang they'd make him spawn more often like Jr.Balrog, but he's never alive. No reason for him to have a low spawn rate if his drops aren't even interesting by today's standards anyway.