Rules as written, p. 12, emphasis mine:
If your Life points fall to zero (as a result of this voluntary sacrifice, or at any other point during the game, regardless of the reason for it), you die and disappear from the game at the end of your game turn.
Suppose I have one life point remaining. The player to my left begins their turn and plays a black Morgan card, "Each Knight immediately loses 1 Life Point." Barring being saved by the Grail, what happens? Am I immediately dead and out of the game? Or does play go all the way around the table back to me, where I can take a full turn at zero life points, and then die at the end of my turn? The latter seems to be what the rules indicate, but that seems rather... wrong... for this otherwise unforgiving game.