Tog Rustsprocket

Tog Rustsprocket is a gnome located in Kharanos in Dun Morogh.

When a Level 10 warlock talks to him, he'll have a conversation text (ie, not a quest) that says:

"Stupid snow... Hey you're, aren't you? I've just received a message asking for you."

Then if you select "What message?", he'll direct you to Lago Blackwrench. Lago will offer you the warlock only quest:, a quest chain leading to learning the Summon Voidwalker spell.