Remus raised an eyebrow at that, knowing the school probably hadn't grown so modern since his own school days that it would allow students to duel in the halls. Hell, they weren't even really allowed to cast spells in the halls, although Prefects and the Heads had to sometimes in order to stop the other kids' foolishness.
Not that such rules had ever applied should one of the Marauders run in to Severus Snape in the halls. But then, they'd tended to live by their own rules even then.
"A huge noise is usually a sign something's gone wrong, unless you were casting some sort of explosion or concussion charm. Your spell and his likely collided or interacted with the schools wards in some way they didn't like! It'd be interesting if you could remember what combination of spells you each cast, just to note that reaction! Although, I suppose I shouldn't be encouraging the fight in the first place."