8 Eyes was developed by Thinking Rabbit and published by Taxan, released for the NES in 1990 as an action-platformer following a knight named Orin traveling to eight castles across Europe to recover jeweled orbs stolen by a corrupt duke, accompanied by a trained falcon that assists in combat. Players wield a sword for close-range combat while directing the falcon to attack distant enemies, and can select which of the eight stages to tackle in any order, a structural choice that gave the game a loosely nonlinear flow uncommon among contemporary NES action titles. Its castle-based level design and item-collecting structure drew comparisons to Castlevania, though its swordplay and falcon-assist mechanic gave it a distinct identity within the genre. Never a major commercial success and largely overshadowed by higher-profile action-platformers of the same period, 8 Eyes has since found a modest cult following among NES collectors drawn to its ambitious, somewhat rough-edged take on the castle-adventure format.