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Onyxia is protected by 3 warders and is quite a hard fight to those un-prepared.

Onyxia's Warders are rather tough but should go down easily to any raid that want's to take out Onyxia.

Warder Abilities:

Cleave - Hits everyone infront of the Warder

AoE Fire Attack - Deals a nice amount of fire damage to everyone around the Warder

Given the high amount of damage from the Cleave/AoE it is recommended to only have ranged DPS on them.

The Onyxia Fight is broken up into 3 Phases -

Phase 1 - This fight starts with the MT attacking a sleeping Onyxia at the far end of the chamber.

You should have 2 tanks for this fight, when the MT has aggroed Onyxia they will have to pull her to north side of the room. It is crucial that she is facing North as to not fire breath/cleave the entire raid group.

It is important that people avoid the whelp eggs as they hatch and can interrupt healers and tanks. Have the raid split into 2 groups and move onto the left and the right side of the room.

During Phase 1 Onyixa will use the following attacks -

Cleave - Frontal attack hitting everyone infront of her

Firebreath - Hits everyone in a cone infront of her for a large amount of fire damage

Tailswipe - Hits everyone near her tail for a large amount of damage

The Main-tanks will be knocked out of position everyonce in a while and should make sure to get her into position at all times.

Once Onyxia hits 70% HP Mages, Warlocks, and Hunters should switch to using wands/auto shot to conserve mana for Phase 2.

Phase 2 - Phase 2 has Onyxia taking off into the air thus making her immune to ground attacks. The goal of this phase is to deal as muhc damage as possible as fast as possible. This is to prevent her from Deep Breathing.

Onyxia will use the following attacks during Phase 2 -

She will spit fireballs at random players on the ground

She will use Deep Breath if she stays in the air longer then 5 minutes. If this happens you will almost always wipe after a Deep Breath as it deals massive damage.

Also quite a bit whelps will spawn from the egg alcoves located at either side of her lair. These should be dealt with by rogues/warriors and other classes un-able to do ranged DPS to Onyxia.

Phase 3 - This begin's when Onyxia hits 40% HP Everyone must quickly move into positions against the walls as in Phase 1 and make sure their backs are against the wall.

The MT's must make sure as in Phase 1 get her to the north part of the room and keep her focused on them. If she turns for even a few seconds she can kill quite a few people thus wiping the raid.

Everyone should hold fire until she is firmly aggroed to the Main-Tanks. Also they must all work to prevent being feared around the room.

Once Onyxia hits 5% her damage will spike up and she may kill a tank or 2 but just keep DPSing till she's dead.