I actually like Auto fail a Save on a 1.
Randomness does work against the PC's. But to me, the simple fact that we use dice in this game indicates to me that randomness is a feature, not a problem.
The only compelling arguement against the save failing on a 1 is that the PC's will see more 'Save or Die' situations than the enemies, and sooner or later, they will bite it. As I see it, there are some counter arguements to that.
1) Most such spells are single target spells. The one that I can think of that can multiple targets (Finger of Death), is HD capped. If your throwing that spell at your players where you can wipe multiple targets, you have other problems.
2) If you are using such spells, against a typical party there will be someone who does not have a great save vs that effect anyway, and failing on a 1 is not his problem.
3) The players will have plenty of resources to offset this sort of thing (Spell turning, anti magic field, other specialized Anti Death Spells).
4) When someone does botch their save, and would have succeeded on a 1 if the rules allowed it, the players probably have the resources to bring him back from the dead anyway.
5) If your that worried about drilling a player to be dead with this kind of spell, then why are you equipping your baddies with it? Either you as a DM want a given spell caster to snuff out a PC like a Candle or you do not. If you dont want a dead player, then do not use spells called Power Word Kill.
5a) If you are a player and fear for your characters life, refer to item 3. There is more to making yourself death proof than very high saving throws. Alternatively, if your that worried about these spells, then why not just ask the DM if such spells and effects can be house ruled out? Most DM's are reasonable about removing such things on a "If you dont use them, I wont use them" basis.
And applying only to my campaign and others with similar house rules:
Z ) I rule that a failed save vs this kind of spell drops you to -1 as opposed to being outright dead.
Ultimately, everyone will have their own particular tastes and preferences. I don't run games that specifically require the players to always succeed anyway, and I am pretty forgiving when it comes to allowing players to keep their characters alive in some manner if I can at all justify it. Those that run more story driven games, I think, tend to prefer avoiding having to deal with an unexpectedly corpsified character 2 encounters before their final battle. And if they are worried about that, then why are they using these spells at this time in the first place?.
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