In the Sythdorn Wastelands lies the ruins of Irf Thalor, an ancient city, long ruined by the hunger for power beyond those that should reach for it.  The city is still haunted by the dark magics that were released there.
 
Rifts into the Elemental plane of Shadows still tear open and close within the deeper parts of the city, feeding the undead with energy and tainting any living creature it encounters, turning them into shades or worse. 
 
From time to time, the pulses of dark shadow energy weep into our realm, and it is during these times that I have traversed into the dark city, battling through those corrupted by the dark energies, until I was able to collect the essence of the shadow plane. With careful preparations and the proper wards, I can provide the purest of samples and bring them to you. Corked and sealed in a vial, to preserve its potency. Sufficient for all magical potions, magical studies, and spell components.