He spawns at the top of the tower at ( 381.7, -47.4, 229.5 ) /waypoint 381.7, -47.4, 229.5. (Next to the Corpse Pitch Bridge) This is a very short easy ring event, just clear all the mobs in the tower.
To get to this instance, head to ( 215, -48, 667 ) /waypoint 215, -48, 667 in Commonlands, then head east down the narrow valley from there. The entrance is at ( -4, -48, 729 ) /waypoint -4, -48, 729.
Starting with LU24, access for Bloodskull Valley is no longer required for those with the quest Die Rückkehr des Lichts.
In order to enter the Bloodskull Valley: Maulic's Stronghold instance ALL group or raid members must talk to Amulius Ramio at ( 24, -46, 725 ) /waypoint 24, -46, 725. He is crouching behind a big rock just outside the BSV entrance. Crouch when you speak to him. Then hail him until he goes through his entire dialog. This may entail talking to him two times or more, depending on the conversational choices you make.
Drull is in the fourth wave of a horde of mostly 20^^, they come in large groups of 5-10 it seems. More will aggro after a specific time. If you die, it does not take you out of the instance, keep hacking away until the General shows up, kill him and exit. Keep in mind, you only need to kill Drull, not the entire encounter he is in.
'**NOTE** Do not exit the zone before you are done or you will incur a 12 hour lockout timer before you may re-enter.'
Speak to Cannix. A group of Lucanic Knights will spawn, kill him, and then attack you. Pry your reward from their cold, dead hands.
Note: You must wait for the group of Lucanic Knights to kill Cannix first on the last step before you kill them or your quest will not complete