Doctor Strange has an eye in the middle of his brow.
In Strange's debut story, Stan Lee characterized the yet-unnamed Eye of Agamotto as "an eye such as no mortal has ever beheld." In contrast to the MCU version, it is magical rather than an Infinity Stone. It's Stephen's most potent weapon, capable of acting as everything from a mental probe to a tracking ray to a magical phaser. The eye occasionally pops out of the amulet and settles on Stephen's brow. While this has some significance — the "third eye" of mysticism and parapsychology — it does not appear to increase the Eye's power or effectiveness. It does appear peculiar - Ditko enjoyed making Doctor Strange appear absolutely bizarre.&