Usage of the Dragon Eye is limited to players who are members of the Path of the Dragon covenant.
Using the Dragon Eye causes the player's sign to appear in the worlds of other players, allowing them to summon the user to their world to duel. The host must be unhollowed, but does not need to possess a Dragon Scale, and the area boss does not need to be alive to interact with the summon sign; users of the dragon eye have no such restrictions as to where and when they can place their signs. Players can summon others that are within their soul level +/-(10+10%) of their level; for example, a level 100 player can be summoned by anyone between level 80 and 120.
The winner of the duel is granted a Dragon Scale and souls proportional to the defeated player's soul level. In the event of a tie (where both players die), both players are awarded a Dragon Scale. Despite the nature of dragon dueling, the host may indict the Dragon Eye user if they are defeated.