This is basically the route, I did this on MP1.
Pick "The Black Soulstone" quest and then go to Desolated Sands and search up "Vault of the Assassin" when you enter that zone you will get a checkpoint there, so just leave the game and you will spawn there. Exit it so you can see later on in the Desolated Sands where it is located, then just teleport to town and take the following waypoints.'
WP to Black Canyon Mines - You will find around 1-4 elites here, clear this area
WP to Road to Alcarnus run over the bridge - You will found 1-2 elites here, you should now have 3-5 stacks.
Teleport to town and WP to Desolated sands, check the map and you will see where Vault is if you exited it earlier. Run to Vault of the Assassin and enter it, clear the whole zone there will be around 7-9 elites in this area.
This is basically the run, it usually takes 5 minutes for me to do the whole thing, it's probably really viable on higher MPs aswell, especially in 1.0.7 when we will get more XP for each MP lvl and also higher drop chance of the Demonic Essences.
Tested it on my Wizard and Witch Doctor - http://eu.battle.net...57/hero/3518648
Edited by Zyfoh, 26 January 2013 - 12:46 AM.