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Set:Ashes of OutlandAshes of Outland
Health:40 Health
Artist:James Ryman
Flavor text

Dr. Boom's failed experiment is the source of all this carnage!

External links

Data pageHearthpwn

Ashes of Outland logo.png The subject of this article is part of the
Ashes of Outland's single-player content.

For the alternate warlock hero, see Mecha-Jaraxxus.

Mecha-Jaraxxus is the fourth and final boss encounter in Chapter 4: Battle for Outland of Trial by Felfire Story.

The player controls Aranna, Unleashed.

Hero Powers[]

Of Fel and Hatred(211306).png

Player's hero[]

Aranna, Unleashed(211236).png
Combination Strike(211237).png

Special cards[]


Fel Reactor(211308).png
Hatred Reactor(211309).png
Rusted Voidwalker(211252).png
Demonic Forging(211307).png
Rusted Legion Gan'arg(211246).png
Endless Legion(211250).png
Rusted Fungal Giant(211251).png
Rustsworn Champion(211245).png


Baduu's Final Gift(211397).png
Natural Leader(211378).png
Sklibb, Demon Hunter(211240).png
Karnuk, Demon Hunter(211242).png
Shalja, Demon Hunter(211244).png


The below classes are listed purely for reference, and have no effect on the boss' use of the cards during the battle.

Mecha-Jaraxxus Aranna, Unleashed
Class Card Quantity Class Card Quantity
Boss Rusted Voidwalker 2 Demon


Blur 1
Deteriorate 2 Battlefiend 2
Demonic Forging 2 Twin Slice 2
Rusted Legion Gan'arg 1 Chaos Strike 2
Endless Legion 2 Immolation Aura 2
Rusted Fungal Giant 1 Netherwalker 2
Rustsworn Champion 2 Spectral Sight 1
Hunter Zixor, Apex Predator 1 Aldrachi Warblades 1
Mage Astromancer Solarian 1 Coordinated Strike 1
Paladin Murgur Murgurgle 1 Altruis the Outcast 1
Priest Reliquary of Souls 1 Ashtongue Battlelord 2
Warlock Mortal Coil 2 Illidari Felblade 2
Kanrethad Ebonlocke 1 Kayn Sunfury 1
Chaos Gazer 1 Glaivebound Adept 2
The Dark Portal 1 Skull of Gul'dan 1
Bane of Doom 2 Priestess of Fury 1
Dread Infernal 2 Inner Demon 1
Felfire Potion 2 Hunter Imprisoned Felmaw 2
Enhanced Dreadlord 1
Warrior Kargath Bladefist 1
Neutral Scrapyard Colossus 1



Of Fel and hatred that started it all, IT'S MECHA-JARAXXUS! AND HE WILL FALL! Go free Outland from all he's spawned! And claim vengeance for all he's wronged!

The leader of the Rusted Legion himself, the penultimate boss fight! He's empowered by a Fel Reactor and Hatred Reactor, whose effects are enhanced each passing turn through his Hero Power when active (by +1 Spell Damage and +1/+1 accordingly). Of course, establishing board control is the highest priority here. Destroy the reactors as soon as possible to stop Mecha-Jaraxxus' benefits, prioritise the Hatred Reactor if you can only destroy one. If left unchecked, the buff it provides to enemy minions played can make a turn for the worse.

Keeping the reactors in check, you should be able to rush him down fairly easy.


Before match

Illidan Stormrage
Cease your moping, our time is nigh! Jaraxxus awaits, come, we fly!


Aranna, Unleashed
Jaraxxus. You're the cause of all this...
Demon hunters? Come take me on! Your doom awaits - OBLIVION!!

Emote Response

Dr. Boom did not build me for small talk. I TALK BIG!

Hero Power (reactors' revival / any spell with Fel Reactor on the board)

Overflowing with power!
So much... Fel!


Dr. Boom never loved me... And I HATED him!
I am a killing machine of indiscriminate destruction, not a time clock.

Turn 1

Aranna, Unleashed
If we defeat Jaraxxus, all of the monsters he built will be free again.
Karnuk, Demon Hunter
Let's save our home!
Shalja, Demon Hunter
When Jaraxxus falls, Outland will know peace...

Turn 3

Illidan Stormrage
Tear this mechanical fool apart, Aranna!

Boss cards

I'll do this MYSELF!
The Dark Portal
Come forth - and KILL!
Endless Legion
You can't STOP US!
Rusted Fungal Giant

Player's cards

Any demon
How DARE you team up with them, they're DEMON hunters!
Baduu's Final Gift
Wait wait wait, that's CHEATING! I won!
Spectral Sight
Stop looking! Just fight ME!
Sklibb, Demon Hunter
That is... a MUSHROOM! Am I a JOKE to you!?
Inner Demon
Oooh. Now it's a REAL fight!

Mecha-Jaraxxus at 20 Health

Dr. Boom programmed, calculated: Fury incarnate. Mechanized hatred!
Aranna, Unleashed
Powered by hate? This thing sounds just like Illidan.


Illidan Stormrage
Excellent! Our foe is done. Now his minions – leave not a one.
Aranna, Unleashed
But his Legion's wrecked remains— They're victims here, and live in pain!
Illidan Stormrage
They're monsters, all! And so we fight. I'll purge this wasteland–
Aranna, Unleashed
That's not right!


Mecha-Jaraxxus represents a version of the man'ari eredar Lord Jaraxxus that has been rebuilt by Dr. Boom for unclear purposes. This version of the eredar lord is unique to Hearthstone.

In Ashes of Outland, Mecha-Jaraxxus is the leader of a new organization called the Rusted Legion and the main antagonist of the Solo Adventure Trial by Felfire. Supposedly, Mecha-Jaraxxus is a failed experiment that Dr. Boom never bothered decommissioning and was left to his own to assimilate every living being in Outland into destructive machines.


Mecha-Jaraxxus, full art

Patch changes[]