"The blood shall be a sign for you on the houses where you live; and when I see the blood I will pass over you, and no plague will befall you to destroy you when I strike the land..."
- As of 1.0.3 'open' does not work as stated. Either the area needs to be faction controlled, it's on a timer, can only be opened at day/night, etc etc ad infinitum. Could be the open key has changed as well. The 4 platforms still exist, with a fore and aft area, and the mini-volcano plinths are still there as well.
There are four stones in front of the door to this lair. The stones have a stump at the back, me and my guild found out that if you stand on the third stone from the left facing the lair door, you receive a glow. After receiving the glow, you will be able to highlight the stumps and activate them, they are called "plinths" and emit a volcano of colors to show they are activated.citation needed After all four are activated the door opens revealing Krela a lvl 31 HERO mob.
The lair contains a vampire.
Drops 31 level rare belt
My Warband and i attempted this Lair and found that at about 5:00 AM game time the stones became available for activation. at 5:30 AM game time Krela Despawned on us. So it looks like you have 30 seconds to kill her. (Type /time) in game to get the currently time, and judge the by sky to tell if its AM or PM.) This account, however, is just one experience. Others who have tried this have not gained entrance. It is likely that there are other conditions required to gain access and that Krela simply despawns at 5:30 (sunrise, she is a vampire) no matter what.
It appears that there may be a hidden cooldown on being able to access this lair. After gaining access with another warband I tried waiting for the day to "recycle" back to 5AM at which point I was unable to re-activate any of the stones. So it might be that even if you gain access to the lair she still may go onto a cooldown even if she has not been killed. (For us she de-spawned just before 5:30AM, in-game time. We were not yet in combat with her at that point when she de-spawned.)
Taken from the from 1.2.1 patch notes from the Warhammer Online website. - "* Lair of Krela Darkshroud: Krela Darkshroud will no longer despawn shortly after being spawned. She will remain spawned until killed."
There is a video on YouTube, the video shows how to open the lair and the actual fight with Krela Darkshroud.