Peacekeeper's silverlight Blade

Peacekeeper's Silverlight Blade, this oversized handle ends in an ethereal dagger whose surface shimmers with extraplanar energies, the silvery metal crossguard, grip and pommel seem to retain a perpetual shine. The pommel itself is set with a Star Saphire, which glows with some internal power. This weapon's damage scales on intelligence. The Peacekeeper's Silverlight Blade normally appears as a dagger, but as a swift action it can grow in size to a short sword, long sword, or great sword. This transformation requires a 13 int check to call upon the magic of the weapon, and provokes an attack of opportunity upon failure. Upon a critical hit, rather than dealing critical damage as per usual the wielder can instead choose to increase the weapon up to it's maximum size from it's current size, rolling damage as if he's successfully landed an attack with each form the weapon can take, and then add twice their damage modifier to the damage total damage.

Upon resolving critical effect, you may treat this as an Impaling Critical or pull the weapon free and treat it as if you've just performed an impaling critical (victim takes damage equal to weapon's damage dice plus weapon properties.)

This weapon is always treated as a Ghost Touch weapon, and ignores Damage Resistance. When using the Star Sapphire in the pommel as a spell focus, you gain a +1 circumstance bonus to concentration checks.