This spell functions like arcane eye, except that it uses an ioun stone as a visible scrying sensor. The ioun stone moves at the same rate as an arcane eye, and may pass through holes or spaces as small as 2 inches in diameter. It can enter another plane of existence using a gate or similar portal, but the caster loses contact with the sensor should this occur. The enhanced ioun stone has AC 24, 10 hp, hardness 5, fly speed 30 (perfect), and a +16 Stealth bonus. The stone does not provide you with its normal benefits while you are using it as a scrying sensor.