I haven't try using the horns in MHF2. Can you even fight with it? It seems to me like a support item more than a weapon. Yeah, you can fight with it, kinda like a hammer. You can also attack while you're playing music, too (playing music = raising stats and gaining effects) With the basic horn, you can do things like raise attack, make attacks harder to break, raise speed, gain infinite stamina, and cancel wind.