mitigating the chance of a 20 on a save

[sreservoir]

I am trying to make a psionic sandwich (sort of). now, it can be done out of WBL at 4th level: power stones of astral seed and mind switch should cost 5150 gp.

this requires the vessel to fail a Will save. it is easy to ensure that it passes only on a 20. the problem is, once we get there, it is actually quite difficult to ensure that the vessel doesn't succeed -- no matter how hard you try, allowing a single save means failure 5% of the time, which is a really bad idea when you just spent your whole WBL on it and you're likely to die if it fails.

so tell me. how can one reduce the chances of auto-successes cheaply, probably by forcing rerolls, but outright making it not auto-succeed work.

(I thought unconscious -> willing -> auto-fail will, but I can't seem to find rules to support that.)

[NNescio]

I am trying to make a psionic sandwich (sort of). now, it can be done out of WBL at 4th level: power stones of astral seed and mind switch should cost 5150 gp.

this requires the vessel to fail a Will save. it is easy to ensure that it passes only on a 20. the problem is, once we get there, it is actually quite difficult to ensure that the vessel doesn't succeed -- no matter how hard you try, allowing a single save means failure 5% of the time, which is a really bad idea when you just spent your whole WBL on it and you're likely to die if it fails.

so tell me. how can one reduce the chances of auto-successes cheaply, probably by forcing rerolls, but outright making it not auto-succeed work.

(I thought unconscious -> willing -> auto-fail will, but I can't seem to find rules to support that.)

Wait... are you trying to use this offensively?

[sreservoir]

no, it only needs to happen once. but it would suck if it failed that first time because loss of 5150 gp and needing ten days to reform is ... not the best idea?

[Calanon]

I am trying to make a psionic sandwich (sort of). now, it can be done out of WBL at 4th level: power stones of astral seed and mind switch should cost 5150 gp.

this requires the vessel to fail a Will save. it is easy to ensure that it passes only on a 20. the problem is, once we get there, it is actually quite difficult to ensure that the vessel doesn't succeed -- no matter how hard you try, allowing a single save means failure 5% of the time, which is a really bad idea when you just spent your whole WBL on it and you're likely to die if it fails.

so tell me. how can one reduce the chances of auto-successes cheaply, probably by forcing rerolls, but outright making it not auto-succeed work.

(I thought unconscious -> willing -> auto-fail will, but I can't seem to find rules to support that.)

You could always smack it with enough negative levels so that it fails no matter what

[Glimbur]

You could always smack it with enough negative levels so that it fails no matter what

Nat 20 auto-succeeds on saves and attack rolls.

It's probably impractical to get an Unluck(Spell Comp) spell on your target, but that would drop the odds of their success from 1/20 to 1/400.

A Fatespinner (C Arc) could force a reroll but I suspect you can't easily get a 9th level character to help you.

[sreservoir]

huh, SpC unluck is one level lower than the CArc version. probably still impractical, though.

[Flickerdart]

(I thought unconscious -> willing -> auto-fail will, but I can't seem to find rules to support that.)
Unconscious creatures don't get saves specifically against "willing creature" spells (because there is normally no save anyway). If the spell doesn't target willing creatures exclusively, there's no advantage in using it against an unconscious target.