Chekov's Spell -- This spell has a two-fold effect. The first is to make the target item almost-unnoticeable to anyone not specifically looking for it. The second is that someone who has seen the item will remember it when they encounter a situation that would be perfectly solved by use of said item.
The ancient Empire of the Golden Crystal fell so long ago that little is known of them besides their legendary magical power. Supposedly, in the Golden Age of the Crystal Empire, cities were filled with enchantment, spells far beyong the ability of modern magi.
A tomb robber has returned to civilization with something never seen before: Ceramic vials of reddish dust that supposedly enhance a magician's power tremendously when the dust is sprinkled upon the floor of his workroom. The rogue selling the vials claims that they were recovered from a ruin of the Crystal Empire, but can he be believed?