This page covers a healer-focused strategy for Hydross the Unstable in Serpentshrine Cavern in The Burning Crusade. 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, combat log information, and Dungeon Journal information. I'll continue to update it as-needed.

General Mechanics and Abilities

During this encounter, players will be switching Hydross between two forms to manage a damage taken increase effect applied to all players.

• Switching between forms resets Hydross' threat. Hydross cannot be taunted.
• A tank switch will occur whenever Hydross changes form.
• Water Form
  • Hydross takes this form any time it's near the purification pylons and has the beams channeling into it.
    • When switching to this form, four Pure Spawn of Hydross spawn. These deal frost damage to the tank with their melee attacks.
  • Immune to frost damage.
  • Avoid the impact location of Water Tomb, players hit are stunned and take light damage over time.
  • All players gain Mark of Hydross, gradually increasing frost damage taken.
• Poison Form
  • Hydross takes this form any time it's away from the purification pylons and does not have the beams channeling into it.
    • When switching to this form, four Tainted Spawn of Hydross spawn. These deal nature damage to the tank with their melee attacks.
  • Immune to nature damage.
  • Targets random player with Vile Sludge, reducing healing done and damage dealt, and dealing light damage over time.
  • All players gain Mark of Corruption, gradually increasing nature damage taken.
• After 10-minutes, goes Berserk, greatly increasing attack speed and damage dealt.

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Resistance Levels

• Tanks:
  • ~365 Frost or Nature Resistance for Hydross tanks
  • ~150+ Frost and Nature Resistance for Spawn of Hydross tanks
• DPS and Healers should use as much Nature Resistance as possible without sacrificing other stats.

Healing Notes

Quick Notes

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

• Use Cooldowns
  
  • when Mark of Hydross/Mark of Corruption are highest, especially to keep the tank alive
• Other things to watch for
  • It's very important that transitions between forms go smoothly. Ensure you're not pulling healing aggro during the switch.

Debuffs to Track

Major

• Water Tomb incapacitates players and causes them to need additional healing.
• Vile Sludge causes players to need additional healing.

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Useful Addons

DBM Settings

Below are the DBM settings I'll be using for Hydross the Unstable in Serpentshrine Cavern. You can set them up however you'd like, but these ones should work well as a starting point.

Healer DBM Settings for Hydross the Unstable

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