Flash

Flashes are normal elemental ghosts and a type of Purple Puncher found in Luigi's Mansion. Ice protects their hearts, so Luigi must melt them through capturing a Fire Elemental Ghost and spewing fire. Then, the Flash will become vulnerable to the Poltergust 3000. The Flash appears only in the Hidden Room, Kitchen and Roof, although two of them are encountered in the Butler's Room during the blackout along with two Gold Ghosts. The Flashes first appeared in the Hidden Room in all except three chests.

Luigi's Mansion (Nintendo 3DS)

 * In-game description: "A Purple Puncher with the Ice Element. Vulnerable to fire."