Archdemon: How to deal 1B damage

Presentation

The Archdemon is found at the end of any chapter of the event
You can fight him as much as you want, but you need to restart and complete a chapter every time
The buffs you buy from the workshop also count for this fight
You get a chapter-specific damage multiplier (10% - 100%): the higher the chapter, the higher the bonus
Nexters have increased the amount of extra-levels for the amulet of battles. It should not affect the price to beat chapter 7, but it has obviously been designed to increase the cost to rank against the Archdemon!

Using the same setup, you will always get the exact same damage
Using the same setup, every player will always get the exact same damage
The slightest change can cause the result to differ greatly. Sometimes lowering a hero yields improvements
But is it because the game uses a different seed, or because attack orders differ?

Last time we used the attack-only talisman* but it has been removed, so we need something else, probably involving Byrna or Adam.

Also it is no longer possible to datamine the top rankers' teams - sorry folks!

SonGoku publicly revealed the mother team everyone used after that, thanks to him. :)

I	785M	150 buffs	⧉	SonGoku (team), Jaya Daniel (pets), Jim, Carrot Muncher (orange martha)
III	791M	100 buffs	⧉	250F
IV	1000M	230 buffs	⧉	3V1
VI	1000M	200 buffs	⧉	Jim
VI	1600M	200 buffs	⧉	Manna
VII	9194M	490 buffs	⧉	Tom Bombadil
VII	3860M	290 buffs	⧉	Clan Glenfell Olympus
VII	5100M	350 buffs	⧉	Crazy Jhu

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