This page covers a healer-focused strategy for Onyxia in Onyxia's Lair. While it's tailored for healers, other roles may also find the information useful. If you have any suggestions or feedback, you can leave a comment below or tweet @PrestonDvorak.

This guide has been updated and maintained based on my own experiences with the encounter, logs information, and Dungeon Journal information. I'll continue to update it as-needed.

General Mechanics and Abilities

To enter the raid, each player will need a Drakefire Amulet which is acquired from the quest line that begins with Warlord's Command (H) \ Dragonkin Menace (A).

This is a multi-stage encounter during which players will be fighting against Onyxia and her brood.

All Stages

• Avoid the two hallways of eggs on either side of the room. Entering the hallway will cause several Onyxian Whelps to spawn that must be killed.

Stage One - Onyxia

This stage begins the encounter and ends when Onyxia reaches 65% health.

• Don't stand in front of the boss to avoid Flame Breath and Wing Buffet.
• Don't stand behind the boss to avoid Tail Sweep.

Stage Two - Airborne

This stage begins when Onyxia reaches 65% health and ends when Onyxia reaches 40% health.

• At the beginning of this stage, Onyxia walks to the center of the room and flies into the air.
• While in the air, Onyxia moves between set positions on the edge of the room (north, northeast, east, southeast, south, southwest, west, northwest).
• When Breath is cast, move to avoid the path in front of her that will extend straight across the entire room to avoid the fatal damage when the cast finishes.
• Stay at least 8-yards away from other players to avoid extra damage from Fireball.

Stage Three - Grounded

This stage begins when Onyxia reaches 40% health and ends when Onyxia is killed.

• At the beginning of this stage, Onyxia will land in the center of the room.
• Flame Breath, Wing Buffet, and Tail Sweep continue from stage one.
• Fears all players using Bellowing Roar.
• Periodically spawns Onyxian Whelps from the side hallways.
• The cracks in the ground will spew lava, damaging nearby players.

Season of Mastery Differences

All Stages

• Accompanied by two Onyxian Drakes.
  • Onyxian Drake
    • The tanks will be dealing with the light damage over time from Vicious Rend.
    • Don't stand in front to avoid Flame Breath.

Stage Two - Airborne

• Stay at least 5-yards away from other players to avoid chaining the light damage over time and disorient effect from Engulfing Flames.
• Two Onyxian Warders spawn at the beginning of the stage.
  • Onyxian Warder
    • Dispel Flame Lash (magic) to remove the reduced Fire Resistance effect.
    • Don't stand in front to avoid Cleave.

Stage Three - Grounded

• Onyxian Warders continue to spawn every ~60-seconds.

Resistance Levels

• All players should have as much Fire Resistance as possible without sacrificing their other stats.
• Tanks may need to add Fire Resistance as necessary to make Flame Breath manageable.

Healing Notes

The notes below mostly pertain to progression difficulty, meaning if you out-gear the difficulty you're on or use extra healers they may not apply.

• Healing this encounter is likely to start out relatively easy and get more difficult through each stage.
• Try to avoid healing right when Onyxia lands in stage three to avoid getting aggro before a tank has a chance to. 
• If you get aggro on any Onyxian Whelps, be ready to run to the off-tank.

Debuffs to Track

• Major: Flame Lash (dispel, magic), Engulfing Flames
• Minor: Vicious Rend

Addons

Healer DBM Settings for Onyxia

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