After the drawbridge was destroyed, playing an instrument on the castle level while knowing the tune continued to offer a chance to play it. Then nothing interesting happened even if you were close enough to the former bridge for it to have been useful prior to the destruction. I think the hero could also be given the tune as a divine prayer boon after bridge destruction but I didn't verify that. The player might not know that the tune is no good anymore, but the hero's patron deity should.
24 KiB
24 KiB