Power modifier Q - variable effect based on margin of success

[robkelk]

I want to convert some of the In Nomine abilities to 4ed GURPS. Many of the IN abilities have different effects depending on the Check Digit (CD), which converts to the Margin of Success in GURPS - is there a way in RAW to do this in GURPS?

For example, IN's Seraphim can detect lies. On an CD 1, they learn whether the person is lying; on a CD 2, they also learn which statements were lies; on CD 3, they also learn why the person lied; on CD 4, they also learn what the person thinks the truth is; on CD 5, they also learn whether the person knows the actual Truth; and on CD 6, they also learn the actual Truth. (Obviously, this isn't just the Detect Lies skill.) In GURPS, a CD 1 would be a success by 0, while a CD 6 would be a Critical Success. If somebody wants to work this one out for me, this particular ability is Cosmic-level unstoppable, but is unusable for (margin of failure) hours after a failed roll.

(Edit: There's another, related, question: Is there a limitation in RAW for "unusable for (margin of failure) hours after a failed roll"?)

Most other IN abilities with variable effects also use the 1-6 scale of success, but not all.

[starslayer]

Originally Posted by robkelk

I want to convert some of the In Nomine abilities to 4ed GURPS. Many of the IN abilities have different effects depending on the Check Digit (CD), which converts to the Margin of Success in GURPS - is there a way in RAW to do this in GURPS?

For example, IN's Seraphim can detect lies. On an CD 1, they learn whether the person is lying; on a CD 2, they also learn which statements were lies; on CD 3, they also learn why the person lied; on CD 4, they also learn what the person thinks the truth is; on CD 5, they also learn whether the person knows the actual Truth; and on CD 6, they also learn the actual Truth. (Obviously, this isn't just the Detect Lies skill.) In GURPS, a CD 1 would be a success by 0, while a CD 6 would be a Critical Success. If somebody wants to work this one out for me, this particular ability is Cosmic-level unstoppable, but is unusable for (margin of failure) hours after a failed roll.

(Edit: There's another, related, question: Is there a limitation in RAW for "unusable for (margin of failure) hours after a failed roll"?)

Most other IN abilities with variable effects also use the 1-6 scale of success, but not all.

I can point you in the right direction I think, but not give you a fully stated power.

Start with a weak detect lies, with the malediction enhancement.
add a follow-up (might be called 'side-effect'?) (only works on success > 5) for a stronger version
Add a follow-up to the follow-up (therefore only works on success > 10) for the even stronger version
so on and so forth.

Variable cannot use again is somewhat tricky, I woudl just go with 'cannot be used for <min time> -x%'

[munin]

In general, buy the ability at full strength and add Limited By Margin. If you need to get a margin of success of 6 or more to get the full strength of your ability, that's a -30% limitation.

[Edges]

They look like cool abilities. I'm not feeling up to stating them right now but I'll throw in some thoughts to help stir the pot.

Levels 1&2 look like Detect Lies (of different MoS).
Levels 3&4 look like Mind Probe.
Levels 5&6 look like Oracle or some kind of Divination.

[Kelly Pedersen]

A lot of the In Nomine angelic resonances are going to be tricky, because the information revealed on different check digits is really best represented by different advantages. For the Seraphim, for example, I'd model CD 1 and 2 as Detect Lies, but DC 3 and 4 are really moving out of the level of Detect and into Mind Reading, while DC 5 and 6 are moving into Blessed territory. Offhand, what I'd do is use Link to tie the various powers together, Based on (Attribute) to move them all to the same attribute, and sufficient levels of Reliable to put them at the right numbers (unfortunately, there's no good limitation equivalent to Reliable to simply reduce the activation roll for a power; probably reasonably to price it at -5%/-2 to your roll, though). You'd make one activation roll, and see how many of the powers turned on.

I'm not sure, however, how to limit the constituent advantages so that only some parts of them would turn on, based on the margin. For example, using the Seraphim, the Mind Reading would have one level where it only worked to tell you the reasons a subject lied or told the truth, and if you made the roll a bit better, it would also tell you what they think the truth is. Clearly, that's some sort of Accessibility on the advantage, but how would you price it? I'd start with Rev. Pee Kitty's guidelines on Either/Or limitations, but I can't figure how to tie the margin of success in there.
Edit: Just realized how to do this last bit! Take the appropriate skill modifier limitation, add it to the accessibilities first, then multiply the whole thing. So in the Seraph's case, we'd have Accessibility: Only to determine reason for lying or telling the truth -20% and -3 To Skill -7.5%, added together for -27.5%, and Accessibility: Only to determine why a target lied and what the truth actually is -10% and -4 To Skill -10%, added together for -20%, and then multiplied together for a final limitation value of -5.5%, which I'd round to -5%.