From Ars Magica
Reveal nearby illusions.
Applies True Sight (buff) to the caster, showing entities affected by Invisibility potions, and allows Illusion Blocks to be passed through. The blocks take on their crafted appearance and become passable.
Duration of the buff is dependent of the caster's Casting Mode, 10, 30 or 50 seconds.
1 x Arcane Essence when cast augmented.
Castable by Caster Block