I’m not sure if anyone has already said this but last night I found a speedy way of dealing with Anathema as Moze. I was using Joltzdude’s Iron Bear build with shock + corrosive rail guns and what you can do is blast away to reach the next invincibility phase. When the radiation bubble comes out, jump out and get into the turret. Moze cannot be damaged there so Iron Bear is quickly recharging. When the bubble bursts, Iron Bear is destroyed but you can immediately spawn him again and blast until the next invincibility phase. Rinse and repeat until Anathema falls.
To top it off, I got a nice shock Stinger ASA so I was pretty happy with that.