I received the death sphere curse so that I could help my party complete the first boss in TONG. However, the temp hit points AND the inability to take damage remained with my character for the whole dungeon. I could not die and I was not taking any damage from any mob or boss. The 'curse' did not clear until I left the dungeon.
LEVIATHAN--19.3k Metallic Dragonborn Guardian Fighter Swordmaster Loadouts
Guild--And the Imaginary Friends