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Boss Info

Netherspite is a giant Nether Dragon. He is an optional boss in Karazhan.

1,100,000 HP

Strategy

Netherspite is a very technical fight. If things aren't done correctly, you will wipe regardless of gear level. This is far from your typical tank and spank boss. Throughout the fight, Netherspite will alternate between 2 phases. You have 9 minutes before Netherspite enrages and gains a 500% increase to his damage.

Phase 1 (portals)

This phase is 60 seconds long.
When engaged, Netherspite will begin his phase cycle and summon forth 3 colored portals. They appear in the same locations at the start of the fight, but each subsequent portal phase will change their positions. The trick to this phase lies entirely with the portals. As soon as the portals are up, Netherspite will gain a buff increasing his damage dealt by 200%. Shortly after the portals appear, each will send a beam of energy toward Netherspite. If allowed to touch him, each beam will provide a different stacking buff. The beam will apply a fresh stack every second.

Red Beam
The red beam provides perseverance. It is the tank beam.
If allowed to hit Netherspite, it reduces damage taken by 1% per stack.
If it hits a player, Netherspite will aggro you ignoring all threat. Additionally, the player gains several buffs.

1. Damage taken is reduced by 1% per stack
2. Defense is increased by 5 per stack
3. +31,000 maximum health with -1000 max health per stack

Green Beam
The green beam provides serenity. This is, in general, the healer beam.
If allowed to hit Netherspite, it heals for +4000 health per stack. This can quickly reset Netherspite to full health if left unchecked.
If it hits a player, they gain the following buffs.

1. Healing done is increased by 5% per stack
2. Spell and ability cost reduced by 1% per stack
3. Max mana reduced by 200

Blue Beam
The blue beam provides dominance. This is the DPS beam.
If allowed to hit Netherspite, it provides a buff of +1% damage increase per stack.
If it hits a player, they gain the following buffs.

1. Damage dealt is increased by 5% per stack
2. Healing received reduced by 1% per stack
3. Damage taken by spells is increased by 8% per stack

Managing these beams is key to victory. The major trick is that if you leave a beam, you get a debuff that prevents you from being effected by that beam again until the debuff fades. This requires a bit of coordination in beam blocking. The beams will move in a straight line from the portal to the center of Netherspite. A player blocks the beam by standing in that line.

For the red beam, you should have your MT take it first. You'll then need a secondary victim for the beam. A rogue or hunter or even a paly healer will work. When the MT gets to a point where he has too many stacks to continue, around 30-40, the secondary red beam member needs to jump in and take over. The health buff provided should allow them to survive until the banish phase begins. When the next portal phase begins, those 2 players will be unable to take the red beam again due to the portal debuff. Your OT and another secondary victim will proceed to take the beam. When the portal phase comes around again, the MT should be ready to retake the red beam.

For the green beam, its best to simply ignore the benefits to healing. The temporary reduction to max mana is actually more detrimental to trying to heal in the long run. The trick here is that the ability cost reduction also affects energy and rage costs. By allowing rogues and/or dps warriors to take the green beam, they will be able to deal out more damage and remain unaffected by the man reduction. If a feral druid take the green beam, it should be noted that their hidden mana bar will be affected by the max mana reduction. Just like with the red beam, you'll need to alternate between two blockers due to the debuff. Only two players are needed since they can soak the green beam for the entire duration.

The blue beam is a absolutely huge dps boost. However, for the majority of classes, trying to block for the entire phase will result in death due to the damage taken increase. Warlocks are able to block for the entire phase. This is done simply with drain life. The damage increase provides such a large health return from drain life that the increase in damage taken is ignored. Shadow priests can do the same to a lesser degree thanks to vampiric embrace. Typically though after about half the phase, vampiric embrace will simply not be returning enough health to continue to block. Throw another dps class in to swap with the shadow priest should the incoming damage get to be overwhelming. You'll need at least 2 players to alternate due to the portal debuff and as many as 4 players if you don't have any warlocks. Non-warlock players taking the blue beam will need a lot of healing!! Warlocks taking the blue beam should be sure to toss CoD just before the portal phase ends. With the stacked damage buff, CoD can knock off 5-7% of Netherspite's health!!

There are several abilities Netherspite uses during the portal phase that should be noted.
First, there will be a continuous damage done to all players in the room. This is from nether burn. It will do around 1000-1500 damage every 5 seconds. This requires a lot of continuous raid healing.
The other major ability to watch for is the conjured void zones. These are large black circles that appear on the ground. They'll inflict 1000-1500 damage every 2 seconds to players standing within the circle. Players need to move out of these immediately. Beam blockers should be careful not to loose their beam when moving out of a void zone.

Phase 2 (banished)

This phase is 30 seconds long.
The portals will disappear as Netherspite goes into his banished phase. Void zones and nether burn will cease. However, Netherspite will now use Netherbreath. This will randomly target a single player in the raid as the focus. The breath is a cone attack facing toward the targeted player. The cone reaches all the way across the room and inflicts 4000-4500 arcane damage on anyone caught in the cone. Players damaged will also be knocked back. The trick is simply to spread out and avoid be bunched up. Netherspite can not move while banished. However, he will rotate in place to face the player he is targeting for Netherbreath. The raid should move away from the player being targeted and healers should be ready to heal the incoming damage.

Players should continue to dps throughout the banish phase. It can be difficult to tell who is being targeted in melee. Do your best to stay out from underneath Netherspite's head.

When the phase ends, Netherspite will be temporarily loose as it takes time for the portals to appear again. The tanks should pick him back up until the portals appear.