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From Pathfinder Impossible Magic, which isn't enabled.

Arclord Eye

ITEM 7
Usage tattooed on the body
Bulk —

These tattoos take the form of an eye nestled within a triangle and are usually worn on the brow; their inks are said to be distilled from rare materials found only within the Crux of Nex. However, their popularity casts some doubt upon this claim. When you target a Concealed creature with a magical effect or spell, you reduce the DC of the flat check to 3.

Activate—Open the Eye (concentrate, manipulate)
Frequency once per day

Effect For the next 10 minutes, you gain an imprecise magic sense with a range of 30 feet. This allows you to detect spells, magical effects, and magical items within range. You also learn the rank or level of such magical effects and their traits. Deceptive illusion magic is not detectable by this magic sense.
Pathfinder Impossible MagicORC