Your soul is infused with demonic knowledge, increasing your Mastery by X for 20 sec.
Dark Soul: Knowledge is a warlock ability learned at level 84 for those with the Demonology specialization. It increases the warlock's mastery for a brief period of time.
Use: Permanently teaches you this glyph. While off cooldown, your Dark Soul ability passively grants you 10% of the active effect, but reduces the power of Dark Soul by 10%.
Sell Price: 1
Patch changes
Patch 5.1.0 (27-Nov-2012): Dark Soul is now categorized as a Curse.