The Cracked Blue Eye Orb is used to invade the worlds of those who have committed sins, as an Arbiter Spirit. The orb may take the user anywhere in the game, including Belfry Sol and Belfry Luna. The orb is used up after every successful or failed invasion, however, they are not used up if the invader is suddenly disconnected from the host's world when they have just spawned.
Can only be used by human members of the Blue Sentinels.
Commonly dropped by the Old Knights in Heide's Tower of Flame or gained after defeating another player in a sparring match in the Blue Sentinels. Three are found in the wooden chest near Blue Sentinel Targray. Also, can be purchased for 10,000 souls by Blue Sentinel Targray in NG+. Three are dropped by the red phantoms near the Blue Cathedral in NG+ and beyond.
- On PlayStation 3 and Xbox 360, Arbiter Spirits can invade other players regardless of the version of the game they're playing, which, in other words, means that a person playing the original version can be invaded by a player playing the Scholar of the First Sin-edition, and vice versa (unless they are in a DLC only area).