A creature cast invisibility on itself. We successfully covered it with glitterdust. Can our Warlock/Acolyte of the Skin target the outlined creature with his Fiendish Glare? The source of uncertainty is that Fiendish Glare requires that he "see" the target. We can't see the invisible creature, just its outline.
An acolyte of the skin has the supernatural ability to unnerve opponents with a ferocious glare once per day. This is not a gaze attack, and the target need not meet the acolyte's eyes or even see the acolyte (although the acolyte must have line of effect to the target). Glaring is a standard action that affects any creature the acolyte can see within 100 feet. The target becomes shaken for 10 minutes
A cloud of golden particles covers everyone and everything in the area, causing creatures to become blinded and visibly outlining invisible things for the duration of the spell.