Vortex Fragments are a Hardmode post-Lunatic Cultist crafting material. It is one of the four Lunar Fragments, dropped from the Vortex Pillar during the Lunar Events. The Vortex Pillar drops 12-60 fragments on normal mode, and 18-90 on Expert mode. These fragments can be used to craft an endgame armor set that benefits all types of ranged weapons, and can also be used to create its respectively themed tools, weapons, wings, etc.
Crafting all of the Vortex gear, weaponry, and tools requires 121 Vortex Fragments and 68 Luminite Bars (272 Luminite).