Fahrakin's damage is not shown in his own tab. He performs an ally atatck, the damage dealt that way is shown as dealt by the actual attackers. So you can't really see what he provides to your team in his own damage tab, if you would replace him with a champ that doesn't have an ally attack, the damage of the team members would get lowered.

To see Fahrakins real damage, you would have to add all damage from the ally atatcks to his 8 million, while the real damage of the team members is a bit lower, you would have to substract all damage they deal from his ally attacks from the shown numbers, as that is, somehow, Fahrakins damage in reality and wouldn't be dealt without him.

Dont forget also that he only actually attacks 3x out of 4 turns, while all the others in your team (roughly speaking) can attack up to 5x out of 4 turns (=> once each of their turn + that turn when Fatman does his a3). Even if they have a non-damage skill in their kit, they'll then get 4 attacks for each 4 turns. And lastly, he puts extra crit damage on everyone but himself, further benefitting everyone else's damage but not his own.

Another thing - looking at your blessings, it looks like you have Michinaki running a sub-par choice. You'll want him running Cruelty, to reduce the boss DEF.

I also notice you have both Brogni and Helicath using Brimstone. You don't need both. Brogni is more than enough. Swap Helicath over to either Cruelty or Phantom Touch.

Lastly, in terms of stats, since this seems to be pretty much an unkillable team, I'll assume you don't need the stats for survival - so Helicath should be dropping a fair amount of HP and DEF in exchange for more CDMG and CRATE. 

thanks for the hints. would it make sense to swap Helicath into:

i

Or wait for better gear?

Depemds if you plan to be using helicath elsewhere in non umkillable teams

Arena, Tag-Arena, Hydra, DT, Twins, Dungeons ... ^^

I am in the minority, but view getting a 1key team as a non priority. Especially at the expense of having hydra/tag S tier /great champs built exclusively to CB, and using all your best gear... 

-still running skullcrusher/tower for 2 years...

I totally agree. Let's say you can 2 key UNM and 1 key NM. Using 3 keys a day is no problem. Increasing the team to 1 key UNM would only give you a brutal chest on top with 3 keys used overall. That's low priority in my eyes.