Is immortal fire sorc a thing?

So I have heard of immortal sorceress where you max Energy Shield to super high levels and stack reduction until you take zero damage. I would expect this to be a lightning build. But now on hardcore I found one +3 fire amulet and one +3 Tiara, both with Dr. Would this be viable?

i can tell you that my well geared fire sorc is tanky but certainly not immortal

Actually, you can do this as an Enchantress if that interests you.

You max Enchant, Warmth and Fire Mastery, also TK and ES, and you still have enough points to put into Hydra and min max everything into Energy (easily to do if you run say double Dragon ( Breast Plate, Kite Shield/ Dragon Shield/troll's nest) Flickering Flame ( Diadem or Tiara), and HoJ Phase Blade).
That limits your DR, tho it does allow insane high lvls of Mana with the Regen from Warmth and you can hit like 4k mana with Frostburn and Gloom's Trap, Silkweave, etc.

Throw Conviction on your merc and you are swinging for 70k damage after calculations (its like 48k sheet damage before Conviction).

You would be a Melee build (super fun) immortal to fire with an ES so high not even 10 Souls in the WSK wld be able to 1 shot you. If you wanted to knock some Mana down, you could always run a String of Ears or Verdungo's Hearty Cord, but with an ES that high, just put Cure Helm on your merc (super easy runeword to make on ladder) and then you don't have to worry about poison bleeding through your ES.

Hope that helps.

Just keep in mind that if you are going to find and "immortal" build, and they do exist, your survivability is so heavily tailored that you don't have a lot of room for damage. That's why enchantress works so well with what you have listed as your interests.

Cheers.