Who in their right mind would use a Grand Piano as a weapon!? Well someone has. A normal Grand Piano for a human is actually the Large version of the weapon. Therefore to use a piano of their size, a medium creature needs to use the large version, with the appropriate penalties involved. A smaller, halfling sized piano (a medium Grand Piano), may be used, but even then the user takes a -2 to attack due to the sheer weight and bulk of it all. This stacks of non-proficiency and all other penalties. It is swung around by one of the legs, which swivels and locks to the side to make a handle for this massive bludgeoning device. Toggling between weapon and instrument is a move action which provokes attacks of opportunity.