True seeing

True seeing, also known as true sight, was a divination spell that allowed the subject see things in their true form or location. A divine version of this spell was reversible, called false seeing, and masked the true form of things, generally making them appear the opposite of their true nature.

Effects
The caster had to successfully touch the recipient of this spell and, for a number of minutes equal to the caster's experience level, the subject's vision was greatly enhanced out to a range of 120 ft (36 m). (The older arcane version of this spell had half this range.) Normal and magical darkness were no longer a barrier, illusions became transparent, magically concealed doors became obvious, invisible things became visible, blurred things became sharp, mirror images didn't fool the subject, and displaced and out of phase things were seen in their true location. Polymorphed or transmuted things could be seen in their original form,   e.g., an elf that was really a polymorphed dragon appeared to have a life-sized spectral dragon superimposed on it. The subject could also see into the Ethereal Plane and other coexistent planes.

Additionally, the older divine version of this spell allowed the recipient to determine the alignment of creatures by examining the aura surrounding them.

True seeing did not allow the subject to detect cleverly crafted hidden doors or see through solid objects, makeup and non-magical disguises, fog, or other physical barriers that blocked sight. This spell did not stack with other magical vision-enhancing effects such as scrying or clairvoyance.

When cast in reverse, false seeing caused the subject to perceive things generally in the opposite of their real state. The opulent became shabby, ugly became beautiful, smooth became rough, mangy became fluffy, etc.

Components
In addition to verbal and somatic components, this spell required an ointment be applied to the eyes of the recipient. For true seeing the salve was made of fat, saffron, and a very rare mushroom that was dried and powdered. For false seeing the ointment was made of poppy dust and pink orchid essence mixed in an oil base. For the older versions of this spell, both mixtures cost 300 gp and had to be aged for one to six months in order to be an effective component for this spell. The newer version did not required the ointment to be aged and cost 250 gp.