Prince Tenris Mirkblood was introduced on October 22nd, 2008 as a part of the Scourge Invasion world event — which was itself a precursor to the release of World of Warcraft: Wrath of the Lich King. He could be found in Karazhan secluded in The Guardhouse, behind a Bloodstained Door above the stables where Attumen resides, which can be accessed through the stairs after Attumen, or through the ballroom where Moroes resides. His death is required to loot the papers which are the objective of the quest  . This quest is given by the Argent Emissary in all capital cities and near Light's Hope Chapel in Eastern Plaguelands.
Attacks and abilities
- Melee Attack - Deals approx. 700 damage to a T4-geared tank. This can be healed through with a simple Renew.
- Blood Mirror: The player affected by this takes equal damage Tenris takes. Lasts for around a minute. Hunters can use Feign Death, Rogues can Vanish, Mages can Ice Block, Paladins can Divine Shield and night elves can Shadowmeld in order to get out of this. It is a smart tactic to just stop all DPS until it goes away and he goes back to his original form. Let the tank alone keep aggro and the healers outheal his damage.
- Sanguine Spirit: Tenris will summon damage-immune blood spirits quite frequently during the fight. An additional spirit is also created whenever a player dies. When these reach any player they deal ~6000 Shadow damage. Make sure everyone stays away from them. They are also immune to any type of CC and cannot be killed by any means. Besides doing immense damage to a player, everytime a spirit touches a player they also heal the Prince for 5% of his maximum health.
Clear the circular hallway outside his room, then kite him around the entire hallway. Ranged DPS and healers should stand fairly close to the main tank, to avoid Spirit spawns between the tank/melee DPS and the rest of the raid. Try to slow DPS when Blood Mirror is up, and do not attempt, at any time, to use spells that dramatically increase DPS. (Bloodlust/Heroism, Bestial Wrath, etc.) You will probably want a healer on the Blood Mirror player and another on the tank. Be aware of the Sanguine Spirits, as they do a lot of damage if you touch them. More spirits come as the fight progresses, so make sure the tank and everyone else keeps moving to stay away from them.
If your group is having troubles spreading out in the relatively confined hallway that you have to work with, consider mis-directing or kiting to Moroes' room so you have more room to work with, and more room to spread out. If Moroes' room starts getting crowded you could even still move him next door where there's still more room. This of course requires for all the mobs to be cleared between Mirkblood and Moroes, all the mobs in Moroes' room including Moroes himself, and if you plan on moving him again, all the mobs next door.
- I smell... <race>. Delicious!
- I shall consume you!
- Drink, mortals! Taste my blood! Taste your death!
- He shares name with a random Blood Mage from Warcraft III: The Frozen Throne, it is very probable they are intended to be the same (as both are elves) but by the time of World of Warcraft: Wrath of the Lich King he died and was raised by the scourge.
- It would seem that his presence in the game is a nod to JK Rowling's book "Harry Potter and the Half-Blood Prince," given his having "Prince" as his title and that half-blood is a cross between a "pure-blood" and a "mudblood" (Mirkblood), "halfbloods" having a parent of each, in the book series. Also, the quest is called "Chamber of Secrets," which is the name of the second Harry Potter book.