Gotta Bounce

Easy solo as of DF and beyond (at max level)

1) Start fight, difficulty normal or above.

2) Continuously keep running in circles around the room, you will be slowed and possibly stunned, but you have to keep moving, so keep a speed boost or blink-type ability handy when needed.

3) One boss will start casting a purple smoke ring at your location ( [spell=282395] ), after some time a ball will drop in that location, you cannot let it touch you, the balls will keep bouncing to your current location (hence the keep moving).

4) After the boss cast that spell 10 times, you can kill both bosses. I recommend damaging them throughout the fight so you can just one-shot them when the criteria is met.

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• Unlike what some other people have said, for me the tracking went from red to white when I had all 10 balls up simultaneously
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• You can be hit by them after the criteria is met, as long as you had 10 up at some point during the fight the achievement will count when the bosses die!
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During the fight, [npc=146495] will spawn [spell=282395]es.
These are large purple meteors that will bounce around the room until it hits a player.
The impact radius will reduce everytime it bounces without being soaked. (this will only occur twice).

Simply avoid all crashes until you have 10 and then kill the boss.

You only need to have 10 crashes active at some point during the fight. I highly recommend doing it at the end.

If you track the achievement it will start red and turn white when the criteria is met.

for anyone wondering if its possible to solo - it is. I did it on my 420 ilvl rogue with mythic vault of incarnates gear (although you should not really require much gear) - The whole idea is to avoid as much damage as possible since you would have 90% reduced health and you can be easily one-shotted if stacks of other abilities get high - so the trick is to let Fa'thuul cast a few void crashes and then kill him when you reach about 4-5 stacks of shear mind (or kill him right away if you want to be safe) after that he will become stationary and start a cast that will heal him, use this time to let the shear mind stacks fall off. He will then heal to 20% then you wait for 1 or 2 casts of void crash and kill him again (waiting for 1 or 2 depends on how comfortable you are). I did this while running in a circle on the edge of the platform, doing that when Fa'thuul healed he was about directly opposite to me and by the time he came to me he was casting 1 void crash, then I would slowly dps him down and wait for the second cast at which point I would kill him again. Eventually I had 10 active void crashes and I just killed Fa'thuul again and continued to dps down Zaxasj.

Make sure you kite Fa'thuul to the 3 different relics otherwise they become empowered (although it didn't matter much).