Terraprisma

The Terraprisma is a Hardmode summon weapon dropped by the Empress of Light boss. The weapon will only drop if 100% of the damage dealt to the Empress occurs during the daytime, when she is enraged and all attacks are instant-kill to the player (Like Skeletron, Skeletron Prime, and Dungeon Guardian).

When used by a player, it creates a detached copy of itself and autonomously attacks by swinging and stabbing at nearby enemies. Each instance counts towards the standard minion cap.

Trivia

 * Although its sprite appears to be a Sword, it is actually a Summoning Weapon. This is similar to the Sky Fracture, which looks like a sword, but is actually a Magic weapon.
 * It will only be dropped by the Empress of Light if she is entirely damaged and killed during the day, when her attacks will do a significantly increased amount of damage. If any damage is done to her at night, the Terraprisma will not drop.
 * Despite the weapon's tooltip, the summoned minions look neither like the Enchanted Sword item or the Enchanted Sword enemy.
 * The Terraprisma has the highest base damage of all minion summon weapons, despite being a drop from the Empress of Light, a post-Plantera boss, and having a rarity of.