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Developer items are Hardmode vanity items, wings, dyes, and other items, that were made for particular members of Terraria's development staff.

A random set of developer items can rarely (1/20 or 5% chance) drop from a Hardmode boss' Treasure Bag (except ) in an Expert Mode or Master Mode world.

Trivia

 * Developer items, along with 0x33's Aviators, are the only Expert-exclusive items that do not have the Rainbow rarity.
 * Some items (unlisted) were used by the developers during game testing, and were removed from normal gameplay, making them unobtainable: Red Potion and Zapinator (the Zapinator was later released on, a different version of the Zapinator was re-released in 1.4.0.1, and the Red Potion is available in 1.4.0.1 worlds with the seeds "05162020" or "for the worthy").
 * The developer items were unobtainable before the 1.3.0.1 update, and, if somehow worn, most of the items would inflict a variety of debuffs on the wearer, even if worn in the vanity slot, thus rendering them useless. One of the exceptions to this rule were Red's Wings, which would give infinite flight when worn.

History
Objets de développeur 开发者物品