Gruul the Dragonkiller is the gronn overlord of the ogres of Outland, ruling with an iron fist. He earned his "nom de guerre" (and the emnity of Sabellian) after slaughtering many members of the black dragonflight who had come to Outland in order to aid the Horde of Draenor.
Gruul is the final boss of Gruul's Lair in the Blade's Edge Mountains. He drops Tier 4 Leggings tokens. He is the father of seven Gronn: Goc, Gorgrom the Dragon-Eater, Grulloc, Maggoc, Slaag, Skulloc Soulgrinder, and Durn the Hungerer. He has about 3,375,000 hit points (Patch 2.4.3), although with Patch 3.0.2 this has been reduced by 30%.
This boss is also part of (what used to be) the Serpentshrine Cavern attunement quest  . This quest requires two signets. One of which, the Earthen Signet, drops directly from Gruul. The other, the Blazing Signet, drops from Nightbane in Karazhan. Serpentshrine Cavern no longer requires attunement as of June 20, 2007.
The Dragonkiller Edit
Information taken from the old official site:
- On Azeroth, the black dragonflight has long been hated and hunted by both mortals and other dragons. This is not so on Draenor. Indeed, dragons are not a species native to Draenor. When the infamous Dragon Aspect, Deathwing, discovered the Dark Portal and Draenor, he felt sure that few of Draenor's denizens would dare challenge the dragons. Thus, it was during the Second War that he traveled to Draenor and hid clutches of his eggs all over the world. Returning to Azeroth, he left behind only a small number of drakes to guard the eggs.
- However, Deathwing had made a serious miscalculation by leaving some of his eggs in Blade's Edge Mountains. The gronn living in the area were not pleased by this potential challenge to their sovereignty. Tension soon erupted into conflict. Led by the mighty Gruul, the gronn and their ogre servants proved too much for the outnumbered black dragon guardians to handle. Nearly every dragon was torn from the sky by the diabolic incantations of the Bladespire clan and then impaled by Gruul on the stone spires of the mountains. The bones still scattered about Dragons' End serve as a stark reminder of the black dragons' defeat.
- Today, Gruul the Dragonkiller is worshipped as a deity by the ogres of the Blade's Edge Mountains. His powerful sons ravage both the Blade's Edge Mountains and the plains of Nagrand. Gruul's unparalleled strength and experience in battle would pose a serious threat if he ever chose to attack Horde or Alliance forces in Outland.
Gruul the Dragonkiller is the father of the seven gronn lords of the ogres, and the most powerful of them. Although he seems to be nothing but a cruel brute, he possesses intelligence. In the events unfolded in the novel Beyond the Dark Portal — shortly after Deathwing invaded his home — Gruul was met by the lost heroes of the Second War: Khadgar, Turalyon, and Alleria Windrunner. They were after the Skull of Gul'dan which Deathwing possessed. After that, Gruul and his ogre minions, along with the heroes, challenged Deathwing from his perch in Blade's Edge Mountains — killing his eggs and impaling his lesser black drakes on the mountain spikes. Infuriated by this act, Deathwing landed on top of them and attacked Gruul. Although clearly no match for the mad Aspect's power, Gruul was saved by Khadgar's miraculuous spell when he disassembled some of the adamantium plates that were holding Deathwing's unstable body together resulting in Deathwing's retreat. This led to a clear devastation for the black dragonflight in Outland. The results can still be seen as impaled black dragon corpses all over Blade's Edge Mountains.
- Basic Melee: 3–3.5k at the start of the fight, on tanks. More than 2 attacks per 5 seconds.
- Growth: Self-buff, increases damage done by 15% every 30 seconds, size increased by 10%, can stack up to 30 times (Growth #30 remains for 5 minutes, after which Gruul shrinks back to Growth #1). Not dispellable.
- Hurtful Strike: always hits the second highest aggro target within his melee range; therefore essential that any melee dps classes maintain their aggro level not only below that of the MT, but also below that of the OT. The base damage on Hurtful Strike is 12,350-13,650 (this, of course, is reduced by armor, Defensive Stance, etc.). A Hurtful Strike is performed on average every 20 seconds.
- Reverberation: Occasional zone-wide silence for 4 seconds. Not dispellable, but can be reduced by anti-Silence abilities.
- Cave In: Random AoE which cHurtful Strikeauses ~3000 damage every 3 seconds in the area. The AoE damage is preceded by ground shake in the affected area and is visible on the roof. This occurs more frequently as the fight progresses. Cave In damage counts as physical damage and can be mitigated by armor. Growth also affects Cave In.
- Ground Slam: Zone-wide knockback into a random direction, then triggers the Gronn Lord's Grasp.
- Gronn Lord's Grasp: Stacking debuff after a ground slam that reduces movement speed by 20%, stacks 5 times, then causes the Stoned effect after 5 seconds. This can only be dispelled by complete Immunity effects and Cloak of Shadows (possibly escape artist; Blessing of Protection does NOT work). Players who dispel Gronn Lord's Grasp will STILL Shatter, which makes it important that they still stay away from others.
- Stoned: Stunned. Occurs after 5 stacks of Gronn Lord's Grasp.
- Shatter: After being Stoned, Gruul will shatter everyone, the damage dealt increases if players are closer to each other. This damage is physical, and goes through immunity shields such as Divine Shield and Ice Block. Ranges from 1100 if just within 15+ yards to over 8.5k if very close. Pets do not cause damage or get damage with this ability, but get stunned anyway.
Players will have ~10 minutes to defeat Gruul (he has roughly 3.4 million hp), otherwise the buff stacks will annihilate the tank. At 16+ grows, Hurtful Strike can theoretically one shot your OT, making it vital to keep them topped off after every strike. The fight is basically a dps race, with an emphasis on raid survival.
A high-stamina/high-DPS raid is favored for this encounter. Melee DPS is at a disadvantage, as Cave-ins often spawn on top of Gruul, and they may have to run out repeatedly in preparation for his Ground Stomp.
The focus is primarily on the healers keeping several "tanks" alive, or in the case of dps, simply staying alive. Cave Ins, while becoming increasingly deadly, only tick after 3 seconds, allowing the quick-footed to exit without damage. Shatter positioning is very important, as too many deaths quickly lead to lethally low DPS.
This is one of the few fights where Main Tank death is not an automatic wipe. Tanking duties simply shift down the ladder of offtanks, with the previous Hurtful Strike soaker becoming the MT.
The main priority for the healers should be to keep track of the silence and have 4/5 healers hit HoTs on the tank to stay alive through the silence. This takes some timing and practice.
Gruul can't do any magical attacks, so it's advised to use amplify magic.
If a Paladin in your raid has Improved Concentration Aura, it may help to place that person in a group composed of healers; the Silence duration mechanic can save your raid on Reverberation at a high Growth stack, by reducing the amount of time they are silenced. It's also helpful for resto shaman to have the silence duration reduction talent, as there will be a lot of moving during the fight and Gruul's room is very large.
Rogues can use Cloak of Shadows to remove the "Gronn Lords Grasp" movement debuff. Likewise, Paladins can also use Divine Shield to remove the movement debuff, and mages ability Ice Block remove the debuff as well, but note this does NOT prevent any damage being done because of Gronn Lords Grasp. Druids can shapeshift, but the debuff will reappear 1–2 seconds after.
The Ground Slam knockback does not properly function if the player is on the rocks around the outer ledges of the room. Players there will be pushed only a short distance, if at all.
Shatter will affect targets beyond line of sight, however players can wedge themselves into niches along the outside to avoid being launched inward toward Gruul.
If you land quite some distance from Gruul, you are advised to run straight toward the outer wall, or toward the wall at an angle away from someone if you land near them. If you land between closer to Gruul than you are to the wall, and you can see other characters between you and the wall, move a bit toward the wall but be sure you keep your distance from those who are closer, and watch for tanks who will be moving toward Gruul. The key to a raid surviving Shatter is to trust those behind you to not come too close and kill you, and for those behind others to maintain their distance from those ahead of them. However, because the result of Ground Slam is completely dependent on chance, sometimes even a well-prepared raid will get an unlucky Ground Slam/Shatter combo that leads to a wipe.
Main Tank Death at 1/4 HPEdit
It is common for many guilds attempting to defeat Gruul to lose their MT around 1/4 health on Gruul. This is usually because the designated healers for the group are running low on mana and/or are not properly getting HoT rotations in before the silence. This fight is important for healers to have high mp5 to last a full 8 minutes. Healers should not be asking for Innervate any sooner than 5–6 minutes into the fight.
If your tank dies a lot during the AoE silence...Edit
If your group consists of 3 tanks (which it should because of High King), you designate a main tank (tanking Gruul of course), a Hurtful Strike tank, and a third tank that is also building up aggro (just in case one of the other tanks die). This third tank should Intervene the main tank to take a hit once during the AoE silence so the healers don't have to worry about the main tank dying due to lack of heals. All healers must have HoTs ticking at all times during silence. Priests should have high Mp5 stacked and not require Innervates (however, non-resto druids should still innervate healers at low mana and/or when they call out for it) until the very end, if at all.
Raid-wise you will need an average of 6666.67 DPS to kill Gruul before he reaches 17 Grows (at which point the tank is risking getting killed in one hit), or an average of 266.67 DPS per raid member (assuming a full group of 25).
Assuming your raid has 3 tanks doing about 150 DPS each and 5 healers doing 0 dps, the remaining 17 DPS classes in the raid will need to average about 365 DPS on Gruul.
--Practical Suggestion-- Note: From practical experience, 17 grows is unrealistic unless you are lucky, or your tanks are overgeared. A group should try to DPS him down by grow 13. A typical group will go with 6 to 7 healers as well.
Calculation: Gruul has 3.8 million hit points. End of grow 13 equates to 14 *30 seconds = 420 seconds. Assuming 6 healers, 3 tanks doing 150 DPS, and no deaths due to Ground Slam and Cave-in, the average raid DPS for the DPS group (16) is 8,598 DPS, or 537 dps per DPS player. A reasonable portion of the raid is spent moving and recovering from Ground slam so this is a minimum.
- Be sure when you begin the encounter everybody follows the MT from the initial hallway. The doors close when Gruul is engaged and anybody who does not enter the room will be locked out of the encounter.
- Hunters usually do well in this fight, as they attack from a distance and are not affected much by silence.
- Rogues can use Cloak of Shadows to remove Gronn Lord's Grasp and position themselves away from others before the Shatter.
- Gruul bugs and the gate stays closed after a wipe where someone has hearthed while the encounter was occurring.
- Pets are not affected by hurtful strike or shatter, but do receive stoned and remain stunned for the same duration as everyone else.
- Pets will not be specifically targeted by Cave In, but are vulnerable to Cave In damage.
- Druids can barkskin every shatter and this is a good tactic to minimize damage taken.
- It is important to note that even if you are within melee range, and able to use your special abilities, you may lie outside hurtful strike range. This is good for melee, and could be deathly bad for tanks.
- KTM may report threat inaccurately in this fight, as Shatter damage dealt will increase reported threat on this system. This can cause a problem for melee characters. Set Gruul as the master target to avoid this problem, or switch to Omen.
- Druids make excellent off-tanks. The Hurtful Strike cannot crit, and cannot be a crushing blow, so all the OT needs is armor, health, and threat generation. Druids don't have to rely on getting hit to generate rage like warriors do, and their typical gear will give them very high dodge as well.
- As a ranged DPS class your aggro can exceed that of the OT, as Hurtful Strike will only target a class in melee range. Especially for players with talents that allow them to stand at 41 yards from the target, picking an obstacle to stand behind during the Ground Slam, and announcing it at the beginning of the raid, is very important.
- Zergable at 80 with one tank, 2 healers smallish raid, generally within 2 grows.
- See The Burning Crusade: Guild Progression for the world first kills.
- "I! I am Gruul, greatest of gronn! This my land. My mountains. And you will not take them! You go or end up like children!"
- Come... and die.
- Ground Slam
- No escape.
- Beg for life.
- Killing a player
- No more.
Patches and hotfixes Edit
Hotfix (2007-05-24): "Gruul's hateful [sic] strike will now target the second highest on the threat list instead of the third highest."