From Pathfinder Core Rulebook, which isn't enabled.

Faerie Fire

SPELL 2

Traditions divine, occult, primal

Cast

Range 120 feet

Area 10-foot burst

Duration 5 minutes

All creatures in the area when you cast the spell are limned in colorful, heatless fire of a color of your choice for the duration. Visible creatures can't be Concealed while affected by faerie fire. If the creatures are Invisible, they are Concealed while affected by faerie fire, rather than being Undetected.

Pathfinder Core RulebookOGL