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Old 05-19-2016, 09:30 AM   #11
Johnny Angel
 
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Default Re: Using "Either/Or" limitations

I'm glad it was raised from the dead. I'm working on something that this is relevant to.
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Old 05-19-2016, 10:03 AM   #12
Kalzazz
 
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Default Re: Using "Either/Or" limitations

I'm afraid I don't the new example to well, could you break it down please?
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Old 05-19-2016, 11:23 AM   #13
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Default Re: Using "Either/Or" limitations

Quote:
Originally Posted by Kalzazz View Post
I'm afraid I don't the new example to well, could you break it down please?
Instead of multiplying the Disadvantage values together, divide each from 1, add them together, then divide the result from 1. So, for a -20% and -30%, you take 1/0.2 + 1/0.3 (5 + 3.333...). That gives you 25/3 (8.333...), so you take 1/(25/3) which gives you 3/25 (0.12), or -12%.

I think I've seen this suggested before (might have even suggested it myself once, it looks very familiar), as it gives you a value that's less then either Disadvantage alone but isn't as harsh as the -6% the official rule gives you.
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Old 05-19-2016, 11:50 AM   #14
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Default Re: Using "Either/Or" limitations

You might as well use this formula that seems simpler to remember.

Multiplication divided by sum

A*B/(A+B)

In the example: (-0.2 * -0.3) / (-0.2 + -0.3) = 0.06/-0.5 = -0.12 = -12%

If the sum is equals or greater than -1 then new formula is worse than the older one!

For example, with the original formula if you compound -80% and -80% the result is -64%. But with the new formula (inverse of the sume of inverses) the result is -40%!
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Old 05-19-2016, 02:09 PM   #15
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Default Re: Using "Either/Or" limitations

Quote:
Originally Posted by Varyon View Post
Instead of multiplying the Disadvantage values together, divide each from 1, add them together, then divide the result from 1. So, for a -20% and -30%, you take 1/0.2 + 1/0.3 (5 + 3.333...). That gives you 25/3 (8.333...), so you take 1/(25/3) which gives you 3/25 (0.12), or -12%.

I think I've seen this suggested before (might have even suggested it myself once, it looks very familiar), as it gives you a value that's less then either Disadvantage alone but isn't as harsh as the -6% the official rule gives you.
It's also the formula for combining resistors in parallel in a circuit (which is a decent analogy, because you are being "resisted" by one limitation or the other.)

EG: if you have a 5 ohm and a 10 ohm resistor and they are in parallel, they have a combined resistance of 1/[1/5 + 1/10] = 1/[3/10] = 10/3 = 3.333 ohms, because a 5 ohm traffic jam here and a 10 ohm traffic jam there is as bad as neither.

Dunno why I felt like pointing that out.
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Old 05-19-2016, 03:49 PM   #16
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Default Re: Using "Either/Or" limitations

Please note that this wasn't a new rule that I created; it's just the existing rule from the Basic Set phrased in a way that's easier to wrap one's head around when discussing limitations rather than enhancements.

As such, if you (cylys_aea) are suggesting this as a house rule, it seems like a reasonable one. I'd have to sit down with it for a bit before I was comfortable endorsing it, but at first glance it seems solid. But if you're saying that this should have been the canonical rule, I'd disagree; it's not the mandate of Power-Ups books to significantly rewrite or revise the Basic Set.
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Old 05-19-2016, 05:22 PM   #17
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Default Re: Using "Either/Or" limitations

PK, that's perfectly fair on not wanting to change what's in Basic. That said, let's look at this suggestion as a house rule. The issue with the canonical Either/Or limitation is that for small limitations, it seems to give much too small of a return. Let's look at some examples:

"Costs 1 FP or 1 HP" winds up at -0.5%, which even if you accept that the canonical prices of those limitations are fair, is way too small. In general, the Either/or rule dramatically undervalues choosing between two small limitations, something that's bugged me for a while. cylys_aea's house rule gives -3.33%, which if you consider the canonical -5% and -10% values, seems about right.

On the large limitation side, let's look at two -80% limitations. The canonical value is -64%. This seems about fair. -80% limitations are pretty crippling and having to choose one of two is still pretty bad. cylys_aea's method gives -40% on the other hand. This seems pretty harsh to me.

As a final class of example, I'm going to look at two Accessibilities using the chart in Powers. At the large limitation end of the spectrum, we have two -40% limitations which mean the power works 1-6% of the time. Then, if you can choose between two cases like this, the power should work 2-12% of the time (to one digit). This gives a -35% to a -40% limitation. PK's method gives a -16% limitation while cylys_aea's gives a -20% limitation. On the small limitation end, we'll look at two -15% accessibilities, which each make the power work 57-68% of the time. Together, the power will work 82% to 90% of the time, or a -5% limitation. The official ruling would make this a -2% limitation, while cylys_aea's would make it a -7.5% limitation.

Hmm. It's not really clear which of these two is producing fairer results. My feeling is that cylys_aea's seems fairer on small limitations, while the official one is fairer on large limitations. Neither one seems to work well at both extremes, nor do either line up with the accessibility chart.

Result of analysis: INCONCLUSIVE.
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Old 05-19-2016, 08:15 PM   #18
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Default Re: Using "Either/Or" limitations

We need to build a function that coverts the equation from one to the other method when your net it greater or less than 1.
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Old 05-20-2016, 09:22 AM   #19
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Default Re: Using "Either/Or" limitations

What about Alternative Disadvantages?

The example is a creature with snail-like eyes on antennae. If it doesn't have 360 degree vision, it's more like Tunnel Vision (retracted eyes) with alternative Easy to Hit Eyes (eyes on antennae).

How would you build such disadvantages?
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Old 05-20-2016, 10:17 AM   #20
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Default Re: Using "Either/Or" limitations

I've been wondering what the Limitation that Warp has (and Power & Breaking Blow as well), with prep time buying off penalties then later adding bonuses. Knowing this, you could buy that Limitation off for a more generic Warp, or you could use it to apply to other abilities.
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