Halfus Wyrmbreaker is the first boss your raid will encounter within the Bastion of Twilight. He is one of Cho’gall’s henchmen, tasked with bending various dragons to his boss’ will. Halfus has one already converted dragon, a Proto-Behemoth, which serves as his guardian; throughout the encounter this Proto-Behemoth will spew fire down on your raid from the air.

Also on Halfus’ balcony, there are 4 imprisoned dragons of various types, and a caged pack of dragon whelps. Each week, 3 of these 5 will be interactive while the other two are debuffed with Unresponsive(dragon/whelp), and cannot be engaged. The combination is random, but will not change until the weekly raid reset. The interactive dragons can be freed (doing so starts the fight, so don’t do it before you’re ready). Each interactive dragon grants Halfus a buff or ability, meaning that the boss’ ability list changes each week. When freed, the dragons attack and debuff Halfus, before being mind controlled and attacking the raid. Each dragon has a different debuff, and their debuffs interact with the abilities they give Halfus, so coordinating which will be freed and when is key to defeating the encounter. Once a dragon – or whelp pack – is mind controlled, it will need to be tanked and killed, so you can’t just release them all at once; your tanks and healers would be overwhelmed.

The dragons and their respective debuffs are as follows:

Slate Dragon – 14.9 million HP in 25 player/ 4.1 million HP in 10 player

Stone Touch
Once you free the Slate Dragon, he will apply this debuff to Halfus, before the boss mind controls him. Stone Touch stuns Halfus for 12 seconds, every 35 seconds. While it will not stop Halfus from using Malevolent Strikes, this debuff gives your tank healers time to patch up the debuffed tank, and also makes it easier for your tanks to swap duties safely. It will persist on Halfus even after the Slate Dragon is killed.

Nether Scion - 14.9 million HP in 25 player/ 4.1 million HP in 10 player

Nether Blindness
Once you free the Nether Scion, he will apply this debuff to Halfus, before the boss mind controls him. Nether Blindness reduces Halfus’ chance to hit, melee attack speed, and damage done by 25%. It will persist on Halfus even after the Nether Scion is killed.

Orphaned Emerald Whelp pack - 1.8 million HP in 25 player/ 518k HP in 10 player (per Whelp)

Atrophic Poison
Once you free the Whelps, they will each apply a stack of this debuff to the Proto-Behemoth (for a total of 8 stacks), before the boss mind controls them. Each stack of Atrophic Poison lessens all damage done by the Proto-Behemoth by 750. The debuff stack will persist on the Proto-Behemoth even after the Whelps are killed.

Storm Rider - 14.9 million HP in 25 player/ 4.1 million HP in 10 player

Cyclone Winds
Once you free the Storm Rider, he will apply this debuff to Halfus, before the boss mind controls him. Cyclone Winds slows Halfus’ Shadow Nova cast drastically, making interruption possible. It will persist on Halfus even after the Storm Rider is killed.

Time Warden – 14.9 million HP in 25 player/ 4.1 million HP in 10 player

Time Dilation
Once you free the Time Warden, he will apply this debuff to the Proto-Behemoth, before the boss mind controls him. Time Dilation slows the Proto-Behemoth’s Fireballs enough that players have time to react and move away from the areas targeted. The debuff will persist on the Proto-Behemoth even after the Time Warden is killed.

Additionally, freeing any of the dragons will create a stack of Dragon’s Vengeance (10/25 player version) on Halfus, increasing his damage taken by 50% per stack. This debuff will persist even after the dragons are killed, and without it your raid will not be able to kill Halfus before he berserks.

Group
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2 tanks – You will need two equally capable tanks to handle Halfus and the dragons, with exact duties depending on which are active for the week. If the Slate Dragon is active, they will need to coordinate a rotation for tanking Halfus, since he will use Malevolent Strikes.

3-4 healers – Bring at least 1 tank healer for each tank, and 1-2 raid healers to counter raid damage.

4-5 DPS – There are no specific limitations to what DPS you bring, aside from having 2-3 players with reliable interrupts during weeks when the Storm Rider is active.

Abilities
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Halfus Wyrmbreaker

32.4 million HP in 10 player

Bind Will
Halfus will use this ability on any dragon or whelps freed by your raid. It happens in a scripted series: you free the dragon/whelp pack, it applies a debuff to Halfus or the Proto-Behemoth, and then Halfus uses this ability to mind control it and it attacks your raid.

Furious Roar
Once he has been damaged to 50% of his HP, Halfus will begin to use this ability every ~35 seconds. Each time he uses it, your entire raid will be hit with a series of stuns. There will be three stuns, each lasting 2 seconds, with just a second in between them. Tanks will need to be topped off going into this ability, and have cooldowns up when it starts, in order to survive. Healers will need to be similarly prepared to use cooldowns to keep everyone from dying. It’s possible to move a step between ticks, but not to use any abilities.

Berserk
Halfus will gain this buff 6 minutes after being engaged in combat. If he’s not dead before he gets this, he will almost certainly wipe your raid.

Malevolent Strikes
Halfus only has this ability during weeks when the Slate Dragon is active. He will use it every 1-3 seconds, stacking a debuff on whomever is tanking him that reduces the effects of healing they receive. This ability makes tank swapping necessary; fully stacked, it reduces healing to the target by 90%, which makes it impossible to keep the debuffed tank alive. Generally tanks will want to swap places at ~6-7 stacks, so that the debuffed tank can still be healed through off tanking one of the dragons or even just the random raid-wide damage effects such as Fireball Barrage.

Shadow Wrapped
Halfus only has this buff during weeks when the Storm Rider is interactive. It enables him to use Shadow Nova.

Shadow Nova
This is the ability Halfus will actually use, and he will do so every ~10-15 seconds. It has a base cast time of 0.25 seconds, but can be slowed to a 1 second cast time by freeing the Storm Rider.

Frenzied Assault
Halfus will only have this buff during weeks when the Nether Scion is active. It doubles his melee attack speed, and will not fade until Halfus is killed.

Proto-Behemoth

Fireball
Throughout the encounter, the Proto-Behemoth will launch balls of flame at random raid members, at a rate of about one every other second. They move very quickly, so unless the targeted player is already in motion, he or she will probably be hit and need healing.

Dancing Flames
The Proto-Behemoth will only have this buff during weeks when the Time Warden is active. Dancing Flames allows the Proto-Behemoth to use Fireball Barrage on your raid.

Fireball Barrage
Every 15 seconds or so the Proto-Behemoth will shoot a bunch of his Fireballs at the same time(~5-6 in 10 player, ~13-15 in 25 player), at different random raid members. However, if you’ve freed the Time Warden, the balls of fire all move through the air slow enough that all targeted players should have time to move out of the way and avoid being hit.

Superheated Breath
The Proto-Behemoth will only have this buff during weeks when the Orphaned Emerald Whelps are active. Superheated Breath allows the Proto-Behemoth to use Scorching Breath on your raid.

Scorching Breath
Every ~30 seconds, the Proto-Behemoth will use this ability to channel fire onto the entire raid. There will be a tick of damage every second for 8 seconds.

Strategy
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Because of the variability introduced by the different interactive dragons, a set-in-stone strategy is not possible. Instead, your raid will need to adjust depending on the combination of dragons available to you that week. For the sake of simplicity, the Orphaned Whelp Pack is referred to as a single dragon below; they function the same way as one of the larger dragons with regards to encounter mechanics. They just die faster to incidental AoE and of course all have their own threat tables.

Generally, you will want to free 2 of the interactive dragons at the start of the fight, and focus-fire one of them down. As soon as the first dragon has been killed, release the third while your DPS are killing the second. This is so that you don’t have to use many tanks, or have any tank handling more than 2 mobs at a time; more than that beating on a tank would likely be un-healable in currently available gear. After the second dragon has been killed, most raids will choose to off tank the last one while burning down Halfus. You’ll want to free the last dragon and off tank it, rather than just ignoring it, because taking the time to do so is less of strain on the raid than the DPS lost if you never get their stack of Dragon’s Vengeance on the boss.

Note that it doesn’t really matter which of the freed dragons you kill first or second; they all just melee swing once released, and have identical health pools. Only the timing of their release matters, since it impacts the damage done to your raid.

If the Time Warden and/or the Storm Rider are interactive, you will want to free them immediately, because both Shadow Nova and Fireball Barrage are deadly if they aren’t countered by freeing the associated dragon. If you are unlucky enough to have both of these dragons active in the same week, still free them both at the start of the fight; just warn your raid that you will be facing a difficult combo and that interrupts and fireball-dodging awareness will be the most important keys to making it through the encounter.

If the Slate Dragon is interactive, make sure your tanks have a plan in place for swapping off tanking Halfus when Malevolent Strikes stacks get to around 6-7. Releasing the Slate Dragon immediately isn’t necessary, but doing so will lessen Halfus’ damage output and make the necessary tank swaps much easier, as well as debuffing the boss with another stack of Dragon’s Vengeance, so you’ll want to do it as soon as your tanks can handle it.

If the Orphaned Whelps and/or the Nether Scion are interactive, make sure your healers are prepared to deal with the increased damage. The Orphaned Whelps will stress your raid healers’ ability to keep everyone alive during Scorching Breath, and the Nether Scion will stress your tank healers by doubling Halfus’ melee speed via Frenzied Assault. It isn’t critical to release either of them immediately, but as soon as you do the increased damage will be basically cut in half as the whelps apply stacks of Atrophic Poison to the Proto-Behemoth or the Nether Scion applies Nether Blindness to the boss. So, if your healers are having trouble keeping up, and you have a tank available that could handle the extra load, go ahead and free them sooner rather than later.

Regardless of which dragons are interactive, you should plan to tank all of them close to the boss once you free them, so that incidental AoE (cleave, living bomb, etc) can hit Halfus while they are being killed, lessening the overall fight duration. There are no directional abilities that limit the position of any dragons or the boss, so take advantage.