Remove 5% life/mana on hit will kill you through immunity.

It seems my luck wasn't everything when I found the 'Moment of Peace' in the room before fighting, as my character still got absolutely dissolved through all my 7k MoM + 4k Health + spamming Life Flasks and Maelstrom flasks.

Turns out the negative affliction remove 5% Mana, Life and Energy shield on hit will kill damage you through immunity, and the boss's lightning spin will trigger that affliction 5-10 times per second.

A little disappointing, Early Access moment I guess.
Hope this gets fixed soon, the affliction should be permanently disabled in the meantime.

Do you mean Moment's Peace boon by immunity?
"You cannot be Damaged until you complete the next room"

Besides damage, there are other ways to harm in PoE.
"Monsters remove 5% of your Life, Mana and Energy Shield on Hit" isn't damage.

okay this is the reason.

Oh my god.

Was fighting the trial boss and had this boon and affliction.

As he started to spin with his lightning damage, I dropped dead with full honour.

https://steamcommunity.com/sharedfiles/filedetails/?id=3412019674