Treasure Bag

The boss loot bag of Expert and Master Mode.

Treasure Bags are consumable loot bags in Terraria that bosses give as a reward in Expert Mode and Master Mode. What a bag looks like and what it holds depends on the boss it came from.

Quick Facts

Type: Consumable (boss loot)
Modes: Expert and Master Mode

Facts from the source article.

Background

A bag holds the boss's normal Classic Mode drops plus one item found only in Expert Mode; the Lunatic Cultist, Dark Mage, Ogre and Betsy are the exceptions and give no Expert-only item. Bags from Hardmode bosses, apart from Queen Slime's, also have a chance to hold a set of developer items. In multiplayer every player who damaged the boss gets a bag of their own. Dropped bags give off light and a special effect so they are easy to find.

What players say: Player verdict on Terraria — Rotten Tweets