Healing tips for Omnitron Defense System

The Omnomnom Something Something

Omnitron Defense System (henceforth ODS) is the first required fight in Blackwing Descent.  It is a council-style fight, meaning that there are multiple targets who all share the same health pool.  In this case, those multiple targets are golem constructs who are protecting the doors to the lower levels where Nefarion and his cronies are waiting to beat on you.  There are four constructs (Magmatron, Arcanotron, Toxitron, and Electron), of which one will be active at the start of your fight, and a second will join in shortly afterward.  Once a second construct is active, the first will put up a shield and deactivate a short time later – and then another of the constructs will join the fight.  Lather, rinse, repeat.  The order that you get these constructs is random and can have a big influence on how much trouble your raid group has with these guys.

I’ll leave the strategizing to you and your raid team, and only offer a few healing specific tips here.  (I would caution you, though, from depending too heavily on the TankSpot video in this case.  It is particularly phoned-in and leaves quite a good number of essential aspects of the encounter under-explained.  Search around the blogosphere if you want something better; or, for the brave and patient raid team, read over the abilities list on WoWhead and then make a few attempts to see what would work best for you.)  The suggestions I’ve written below are based on my observations from the 10-man version of this encounter, though I’m sure a lot of it will hold true in 25-man as well.

Live by RNG, die by RNG.
It’s not that any combination of constructs immediately means you’ll wipe, it’s just that certain groupings are much more complicated to manage and heal through.  To minimize this as best we could, we kept our tanks positioned at opposite sides of the room from one another and assigned one healer to each of the tanks and one dedicated to the raid.

Arcanotron is your new best friend.
When Arcanotron is active, he will occasionally (meaning 2-3 times before he deactivates) cast Power Generator.   This spell will leave a swirling blue pool on the ground underneath Arcanotron and can give him a 50% damage boost if you let him stand in it – which you won’t.  Once the tank drags the boss out of the blue pool, all ranged DPS and healers should run to stand in it so that it will increase their damage done and RESTORE MANA!  The timing on Arcanotron’s activation can make or break this encounter, depending on how much of an issue mana is for your healers.  As a healer, you’re really going to want to make sure you get yourself into these pools every time you see them up.  Well, mostly every time …

Arcanotron is only your best friend when Electron isn’t around.
Unfortunately, there is one construct in particular that calls for the raid to be as spread out as possible.  This is Electron, who casts a chain lightning spell.  When we had both of these constructs up at once, we had to make the choice of whether to forgo the mana regen from Arcanotron’s pools, or risk having everyone standing in the pool get hit by Electron’s lightning.  I’ll be honest – most of the time I opted for the second choice.  Healing through the chain lightning was a price I was willing to pay to get that mana back, but your raid may feel differently.  Talk to your other healers and ranged DPS prior to the start of the raid to decide how you’ll handle this situation if it arises for your group.  Maybe only the healer who is lowest on mana at that point will run into the pool and the others will stay spread out?

If Magmatron casts “Acquiring Target” on the tank, it’s cooldown time.
Magmatron’s high-damage single-target cast, Acquiring Target, can hit your tank.  If and when it does, it’s going to take a CD from your tank and possibly some from your healers as well to keep him alive.

Efflorescence looks a lot like Toxitron’s Chemical Bomb.
Toxitron places a green gas cloud on the ground using his Chemical Bomb ability.  It’s on the ground, it’s green, and your raid still isn’t completely used to Efflorescence yet.  This may be a time to call out in vent to let your group know which thing on the ground is good green, and which is bad green.

Save major cooldowns for a Magmatron + Electron combo.
Getting Magmatron and Electron active at the same time is some bad luck, and it’s also something that’s plenty likely to happen at some point during your attempts on this fight.  Save Tranquility for this combination, and use it after Magmatron casts his AoE damage spell, Incineration Security Measure.  Using Barkskin right before you begin to channel Tranquility is always a good idea so that you don’t miss any ticks due to pushback.

While the first several attempts your group makes on ODS may feel very chaotic and unpredictable, once you memorize the four constructs’ abilities things will be much easier.  ODS isn’t a particularly punishing fight for gear or DPS as it has a generous enrage timer, so it comes down more to execution than anything else.  Stand in the blue pools, stay out of all the bad stuff, conserve mana, and manage your cooldowns.  Best of luck!

Loot

ODS drops a two great pieces for healers.  Security Measure Alpha is a decent choice for a ring with Spirit and Crit.  Much better are the Passive Resister Spaulders with Spirit and Haste – get these if you don’t have your Tier 11 shoulders yet.