The Strobulb, along with the Poltergust 5000, is found in mission "A-1: Poltergust 5000". The first time it's seen, Luigi can see two Greenies steal in from the Poltergust 5000. Luigi chases these two Greenies to the Guard Hall, where they keep giving it to each other, and then leave. Finally Luigi chases them to the Foyer, where he sees that they have placed it atop a chandelier. He must lower the chandelier by going up to it, spinning a wheel-like contraption to lower it, and run down and get it before the chandelier raises back up. Once Luigi does have the Strobulb, he equips it on his new Poltergust 5000, and accidentally flashes himself in the face with his flashlight's new ability.