Blade Phantom's Guide

A blade phantom's guide is a metal rectangle, often on a chain, etched with an image of a warrior in a fighting stance. When you apply a blade phantom's guide to a weapon, it summons a spiritual fragment of a warrior who was adept with that weapon. For 1 minute, you treat your proficiency with that weapon as equal to your highest weapon proficiency. This effect cannot affect a weapon whose level is higher than the blade phantom's guide (11th).