I am playing HC seasonal, so dying is not an option. I know I have to hit the power / conduit pylons at 97 and then run to the edge at 125.

I am playing on DH. I am doing solo, so I have circle of time ammy on my follower.

How much toughness should I am for? - Is 4MM enough? (wraps of clarity, elusive ring, endless walk ring/ammy, tons of resource reduction with the crafted set that gives me 85% dmg reduction when I have 85% resource reduction, etc.)

I am only 900 paragon, have ~2M dmg, and do not use focus/restraint or squirts because I added other gear for toughness - will this be enough dmg?

Are the green meteors that fall only doing psn dmg? If so, I was thinking I would swap out endless walk ring/ammy for a unity and that ammy that makes me immune to psn since those are the main thing that can kill you.

Update - I found out that the meteor dmg is physical so you cant be immune to it. I threw on the fire immune necklace and had flavor of time on follower. I waited until 1,000 paragon, and used a UE build that gave me ~6 billion toughness. The damage was a bit low, but not necessary when hitting the power at 95 and conduit at 99. Never popped on any attempts.

well 6 billion toughness is enough, also you can have 2 cheat deaths, one from passive and one from templar so you should be fine.