Eyepatch is an elderly appearing Host who was active in Westworld 30 years prior to the main events of the show. His narrative involves coaxing guests into going out on treasure hunts with him in the desert, though his persistence can be perceived by many as annoying.
When William and Logan first arrive in Westworld, (it being the formers first time) Eyepatch is thrown off of a cart and into a patch of mud. William helps him up, but Logan stops him and explains he'll try and drag them into "some bullshit treasure hunt".
Later, William and Logan are having dinner in the Coronado, when Eyepatch appears at the bar having a drink. He spots the two of them, and approaches despite Logan repeatedly telling him to go away, instead trying to talk William into the treasure hunt.
Logan finally loses his patience and rams his table knife through the Host's hand, pinning him to the table. Eyepatch, in obvious pain, struggles to pull the knife out of his bleeding hand as Logan taunts him. The pair then leave him, with William in obvious shock over how Logan has just acted. Eyepatch is not seen again in the episode nor for the remainder of the series. Since his appearance is 30 years before the main story, it is unknown what became of him.