Soul of Fright

Soul of Fright is a Hardmode crafting material dropped by Skeletron Prime. They are used to craft several end-game items, including the Flamethrower.

To craft the Drax (or Pickaxe Axe), Neptune's Shell, and Flamethrower requires fighting Skeletron Prime a maximum of twice. To craft all items (excluding console-exclusive items), requires 65 Souls of Fright, so Skeletron Prime will need to be defeated at least twice. Crafting all items (including the console items) requires 132 Souls of Fright, meaning the player must defeat Skeletron Prime at least four times to gather the souls required.

History
Âme de Peur