Blimey, thought Harry suddenly. How was he going to take the Serpent Slayer down into the Black Lake? He wasn’t a very good swimmer, but if he tried to bring the sword along with him, it would definitely drown him. Fine, he’d have to do this task without the Serpent Slayer, but that still didn’t solve the issue of holding his breath underwater for an hour or what was going to be taken from him.