Suspicious Grinning Eye

The Suspicious Grinning Eye is a Master Mode-exclusive drop from the Eye of Cthulhu, with a chance to drop. It summons a Suspicious Eye pet which resembles the Eye of Cthulhu. It normally shows a blue iris and pupil, but when moving at above certain speed the pupil slides up and reveals a mouth, similar to the Eye of Cthulhu's second form.

Trivia

 * The tooltip is a reference to the Suspicious Looking Tentacle item (or Suspicious Looking Eye light pet) and how the name of the pet, Suspicious Eye, is seemingly missing the word looking.
 * While the Suspicious Grinning Eye is equipped, the Suspicious Eye pet will always be in front of the player if they are standing still. After equipping the Suspicious Looking Tentacle, however, the Suspicious Eye pet will be pushed to the other side of the player and Suspicious Looking Eye light pet will hover in front instead.
 * Due to the pet's similarity to the Suspicious Looking Eye light pet, dyeing it with Teal Dye will make it look almost identical.