Mechanical Skull

The Mechanical Skull is used to summon Skeletron Prime, the hardmode version of Skeletron. It can only be used at night, which means consuming this item during day will not spawn Skeleton Prime. It is also unusable when the boss is already present. It can be used in any world, but usually only becomes accessible in a Hardmode World. If Skeletron Prime has not been defeated yet in a hardmode world, all enemies (with the exception of statue-spawned enemies and meteor heads) have a 1/2500 (0.04%) chance of dropping this item. Otherwise this item can only be obtained via crafting.

Trivia

 * The Skull Lantern and Mechanical Skull are very similar in appearance to the skull in the original sprite for Skeletons: Skeleton (original).gif.
 * Like the Mechanical Worm, it looks like a wind-up toy.

History
Crâne mécanique 기계식 두개골