The 机械魔眼 is used to summon 双子魔眼, the advanced and 困难模式 version of the 克苏鲁之眼. It can only be used at 夜晚, which means consuming this item during 白天 will not spawn The Twins. Using another Mechanical Eye while the previous Twins are active will not consume the Mechanical Eye, and a new pair of Twins will not be summoned. It can also be used in a world without Hardmode enabled. If you have not defeated The Twins before dawn, they will flee and the player will not be able to finish defeating them.
If you have not defeated The Twins yet and are already in Hardmode, all enemies (with the exception of statue-spawned enemies and Meteor Heads) have a 1/2500 chance of dropping this item.
- The Mechanical Eye is the only mechanical item with no visible winder.
- 1.2.1：Drop chance now reduced from 1 in 1000 to 1 in 2500.
- 1.2：Now a 困难模式 drop from mobs. Recipe changed.