Vanishing Weapon Fusion
The vanishing fusion can hide its wielder from the sight of one foe. Once per day after making an attack with your weapon, regardless of whether you hit your target, you can become invisible to that target per invisibility for a number of rounds equal to the weapon’s item level. Any attacks you make (even against other targets) end your invisibility as normal. All creatures other than the target continue to be able to see you normally. Only small arms and weapons with the operative special property can benefit from this fusion.