Byrna Event - Archdemon, how to deal 10B damage

Archdemon

The Archdemon is found at the end of any chapter of The Ritual's Price
Battling the Archdemon will get you a cake piece, and you must collect all seven of them
But you cannot collect more than the number of days currently elapsed, so you will have to wait for the end. You can fight once a day, or several times in a row
You can fight him as much as you want, but you need to restart and complete a chapter again

The game keeps the highest score you achieved today
The buffs you buy from the workshop also count for this fight
You get a chapter-specific damage mulitplier (10% - 100%): the higher the chapter, the higher the bonus
The fifty highest scorers earn between 200 and 30k emeralds. The latter certainly look nice, but you would need to spend way more money than they are worth for.

The teams below often require rare heroes or more buffs than the ordinary teams from The Ritual's Price
The provided scores are indicative, since the number of buffs was rarely specified by their reporters. They are not the highest scores ever achieved either
The best teams seem to be only practically available from ch5 and beyond, sometimes at the end of thse chapters. Before that getting the right heroes seems too hard
Best general-purpose talismans are acceleration and pact, but others enable specific powerful combos
The 18B below is likely with 300 buffs, but I do not think there is any cheating here