The 4th Level Abjuration spell, Death Ward, states, in part: "If the spell is still in effect when the target is subjected to an effect that would kill it instantaneously without dealing damage, that effect is instead negated against the target, and the spell ends."
So what happens if someone warded with Death Ward reaches level 6 of exhaustion, "Death"? (Perhaps because they've been wandering lost in the Underdark for a week with no food or water...) By the spell description, the "effect is negated", so it seems to me the character wouldn't die. As a DM, I'd probably say that the character's exhaustion level goes back down to 4 or 5.
So a mid-level cleric, trapped by, say, a cave-in, could postpone their own death by starvation indefinitely. They'd just keep getting thinner and thinner, and more and more dehydrated. Eventually the only way they'd be able to wet their lips enough to cast the spell would be to drink their own blood. And they'd turn into a ghastly, shambling, corpse of a person, and they just wouldn't die...
So what happens if someone warded with Death Ward reaches level 6 of exhaustion, "Death"? (Perhaps because they've been wandering lost in the Underdark for a week with no food or water...) By the spell description, the "effect is negated", so it seems to me the character wouldn't die. As a DM, I'd probably say that the character's exhaustion level goes back down to 4 or 5.
So a mid-level cleric, trapped by, say, a cave-in, could postpone their own death by starvation indefinitely. They'd just keep getting thinner and thinner, and more and more dehydrated. Eventually the only way they'd be able to wet their lips enough to cast the spell would be to drink their own blood. And they'd turn into a ghastly, shambling, corpse of a person, and they just wouldn't die...