Heroic: Atramedes

The heroic mode adds imps called Obnoxious Fiends that need to be killed immediately, as they'll jump onto the back of a random player, and start chain casting a spell that increases that player's sound if not interrupted.

Nefarian also destroys a random gong in the room whenever you ring one, meaning you only have five to work with in total.

Lastly, all of Atramede's abilities make you gain around 50% more sound then they do on normal (On top of already causing more damage then on normal), which can easily make his Modulation deadly if people mess up even a few times.

Does modulation damage somehow depend on your sound lever or smthg else? We sometimes takes 80-90k aoe and its wipe us... Usually its much less.

I want to correct you. Nefarian destroys gongs only on ground phase, on air phases gongs are safe. Fight should go that way: 2 gongs on groung phase (1 ringed and 1 destroyed by Nefarian) + 1 on air phase + 2 ground + 1 air + 2 ground + 1 air + 1 last gong on ground phase = 10, from which 3 are destroyed by Nef. You can work with 7 (seven) gongs total. This means you should kill him in three air and four ground phases, but its possible to live through fourth air phase (with casualties of course) and kill him before 5th Searing Flame, which will wipe you.