Troll Lord Games

I would like a little bit (or a lot) of input on something I've been thinking about all weekend.

Because of my recent background with Savage Worlds, the "flat" nature of the d20 mechanic has bugged me somewhat. Whenever a d20 is used, the probability of each result is fixed (5% each), with hard top and bottom limits. You always know the range you'll roll in, and you have a good idea what the probability of any given result is.

One thing I really like about Savage Worlds is the potential for phenomenal success - mainly due to the "exploding" die mechanic - ie, if you roll the highest number on a given die, you get to roll again and add that roll to the original number, ad infinitum. So, if you rolled a 10 on a d10, you'd roll again and add that to 10. Get a second roll, and roll again, adding 20, etc. While rare, acing rolls like that adds a dimension to the game.

So, I was thinking about what I liked about that, and how it could be implemented in C&C. And I thought about substituting 2d10 (with the exploding mechanic) in place of a d20.

A few things, of course, immediately popped up. The primary one is that the curve of success changes, since rolls are now weighted towards the middle, not evenly across the high-low spectrum. This (in general) makes higher difficultly tasks more difficult, and simpler tasks easier (and higher ACs harder to hit, lower ones easier, etc).

On the other side, it adds two new elements - dramatic success (rolls over 20, possibly via explosion), and dramatic failure (snake eyes). Plus, experience has show that its fun to roll the aces.

So: good, bad, indifferent? Anyone have any thoughts one way or another, or experiences doing something like this?

SavageRobby wrote:
So, I was thinking about what I liked about that, and how it could be implemented in C&C. And I thought about substituting 2d10 (with the exploding mechanic) in place of a d20.

I've thought about doing this actually. It makes rolls more reliable. You'll rarely be a klutz and fail something simple, but it'll also be rare for you to pull off something extraordinary.

As such, it might change the nature of adventurers. Difficult tasks are truly tough, so players may not be as eager to attempt them. They're be more dependence on your modifiers than the luck of the roll.

I think it'd work perfectly fine. I don't think it'd break the system at all.

However, i'm not a fan of the exploding mechanic, because i think it can break encounters. One lucky `explosion' and a well designed encounter is reduced to nothing. That spoils all the fun and wastes the planning that went into it, imo.

But 2d10 on it's own, go for it.

-Fizz

I would do the TORG way: roll 1d20. On a 10 or 20, you roll and add again. Gives a 10% chance of "explosion." However, they do not have a "critical failure" rule, per se, so something like... a roll of 1 or 2 results in roll again, subtract. I also like the idea of a decreasing explosion, so the numbers simply don't get out of hand. This, though, works best in incremental dice... so, for example, on an "explosion" you roll a lower die type (let's be easy, and say d4) which is 25% of further explosion, and that, to a d6, and that (at 16 2/3%) to a d8 (and that, with a 12.5% further) to a d12 (at 8 1/3%) to a d20 (at 5%) and nothing after that. This is both realistic, in a sense, but much more complex. Obviously with incremental explosion dice, the likelihood of continuation drops rather dramatically, and stays random, rather than "flat" which I prefer.

Other, easier ways, are to have "critical values" where, if you roll above some preset number (say, you assign all attack rolls as a critical value of 17) so any 18 - 20 natural roll gets a second roll, but all ability checks are a 15+. Each "step" say, of 6 points of total roll above the "critical value" = 1 level of success. For attacks. this might mean extra damage, and for skills, it might mean doing something normally not possible, like running silently. In this way, you can still have a "you succeeded, but not by 2 steps, so you did not get to run... you are still silent, though" or "ok, well, no extra damage, but you hit." Its a bit more complicated, but easier than the other I suggested.

Its one of the things I like about Legend of the 5 Rings, the exploding d10's. They have even added "specializations" in its 3rd edition for really powerful characters (top end of the spectrum) to even explode on 8 or 9 as well as 10.

It may even have been that way in 2E, but I haven't played 2E for a couple of years now, so I may have definitely forgotten.

Anyway, its doable. I think it will take some tweaking, but with SW as a guideline, I bet you'll quickly get there.

For C&C I wouldn't go for exploding dice.

If your looking for more grit, reliance on ability scores and more realism the bell curve is the way to go. If you want to keep the same range 1 to 20, roll 3d20 drop highest and lowest.

Ooops... double post...

SavageRobby wrote:
Anyone have any thoughts one way or another, or experiences doing something like this?

I already tried to implement something like 2d10 over a value/DC, because of the "bell curve that is more realistic than a flat d20 roll". However, working on that concept, I eventually realized this: whether you use a d20 or 2d10, with a DC to overcome it all boils down to a percentage chance of success. Using the d20 or 2d10 changes the probability outcome, but this can be adjusted so a given task would wield the same percentage of success. As such, where is the difference? The only true difference is that you will get a 20 much more often with a d20 than with rolling 2d10. Other than that, 2d10 is not more realistic than a d20 when you just roll over a DC. It just wields different % chance to successfully roll 1d20 over 15 than 2d10 over 15; but who is to say that having a 75% chance of success is more realistic than having a 62,5% of success? (well, I don't know the probablility of rolling 2d10 over 15, but you see the idea).

Now about exploding dice. Savage worlds was designed with this idea in mind, not C&C. Yet you could probably implement something like that with a few houserules:

1) d20 roll: on a natural 20 you roll another dice to get special added benefits (i.e.: the critical roll).

2) damage roll: when rolling maximum dmg (i.e.: 6 on a d6), you get to roll one more time.

Solution 1 can bring fun to the game, although it will feel different and far away from the SW mechanics. Solution 2, I advice not to use, as it can quickly get out of hand and unbalance the game (especially when it's easier to roll a 4 on a d4, than a 12 on a d12).

Good thoughts so far. Looks like I'm not all that far off base. I was afraid of logging in this morning and see a bunch of flames.
Just to be clear, I was only looking at this for basic d20 rolls - attack rolls, saving throws and SIEGE rolls - not damage or other rolls. I like the idea for basic checks, but I tend to agree that it would hurt the system using it on damage rolls.

Anyone else?

Remember that with 2d10 a +1 suddenly is a lot more valuable than it is to a d20. This means that Prime rolls suddenly become A LOT more useful as do the character's attribute bonuses and any magic items.

Quote:
The only true difference is that you will get a 20 much more often with a d20 than with rolling 2d10. Other than that, 2d10 is not more realistic than a d20 when you just roll over a DC. It just wields different % chance to successfully roll 1d20 over 15 than 2d10 over 15; but who is to say that having a 75% chance of success is more realistic than having a 62,5% of success? (well, I don't know the probablility of rolling 2d10 over 15, but you see the idea).

Not quite... with a d20 you have the same % chance to roll the any value (5%). On 2d10, the odds of rolling a given value are weighted. You're more likely to roll values of 8 to 12 (44%) than you are other values. On a single d20, you have a 5% chance to roll any of those values (or a 20% chance overall).

Meanwhile, your example of 1d20 vs 2d10 with a TN of 15, you're more likely to succeed on the 1d20 (30% chance of rolling a value of 15 or higher) than you are with the 2d10 (15% chance). Then again, any bonuses or penalties are more meaningful to 2d10 than they are to 1d20.

There is a huge difference in moving from a linear distribution to a bell-curve.

The exploding die mechanic did exist in 2e, but my recollection is that it was only for the firearms. However, it was balanced by a misfire chance.

Treebore wrote:
It may even have been that way in 2E, but I haven't played 2E for a couple of years now, so I may have definitely forgotten.

Well, there's the alternative of using 3d6 posted on the d20 Hypertext:
http://www.d20srd.org/srd/variant/adven ... eRolls.htm

Here's a graph of some alternate methods and what they look like:
http://blog.incorporeal.org/media/blogs ... ls-big.png

And a small article about it here:
http://www.frontiernet.net/~jamesstarli ... inear.html

This is also kind of handy if you're thinking of monkeying around with dice: http://www.darkshire.net/jhkim/rpg/syst ... thods.html

Of course this doesn't really address the whole exploding dice idea.

Personally I don't really care about it. Fans and detractors of exploding dice have all sorts of claims to support their position. End of the day, I don't really care much.

If you're really interested in the probabilities, it's a bit harder to offer concrete help. Your best bet is to look for some sort of something that can handle a system like White Wolf or the WEG d6 system. This doesn't do exploding dice, but it's still pretty handy for a lot of dice probability stuff: http://www.fnordistan.com/smallroller.html

cheeplives wrote:
Remember that with 2d10 a +1 suddenly is a lot more valuable than it is to a d20. This means that Prime rolls suddenly become A LOT more useful as do the character's attribute bonuses and any magic items.

This is true. It's been suggested that the +6 difference between prime and non-prime had to do with the standard deviation of 1d20, which is 5.8.

(I don't know how true that is, but it makes some sense.)

The standard deviation of 2d10 is 4.1. So, perhaps the CB should be 12 for primes and 16 for non-primes.

-Fizz

Interesting. Using 2d10, I was looking at making at 10 and 16 (based on someone's recommendation from an earlier thread, but I don't recall who).

SavageRobby wrote:
Interesting. Using 2d10, I was looking at making at 10 and 16 (based on someone's recommendation from an earlier thread, but I don't recall who).

Hmmm... 10 wouldn't seem right to me. 10 is less than the average roll of 2d10 (11). I think the CB ought to be higher than than the average unmodified roll, even for a prime.

-Fizz

With 2d10, you're probably right. 12 would be better.

Not being good at statistics, I wrote a little die roller program. The average of 2d10 is (as we already know), 11. The average of an exploding 2d10 is 12.22. I don't have it calculating the occurrences of individual numbers, but at some point I will tweak it to do that.

Going by what I have seen rolled on the d10's in my L5R game for the last couple of nights your worrying too much. Plenty of 18, 19, and even 20's rolled, as well as 3, 5, 7, etc.... Haven't seen very many 2's though.

Beware of "exploding" types of rules, when different types of dice are involved in the process. For example, the system used in Savage Worlds has a (subtle) bug since highest probability of success are assigned to increasing die sizes. But as the die size increases, the variance of the results increases also. And this fact mixes with the exploding rule in an unpleasant way. The end result is that a character might have an higher chance of success with a LOWER die type rather than an HIGHER one (basically since the chance of rolling the maximum on a die decreases with increasing size). For example, with a target of 6, having a d4 is slightly better than having a d6.

If you plan to use just one type of die, you will not have any problems. You must only tweak the probabilities.

I am (at least for now) convinced not to use the exploding dice. I figure if I want to play Savage Worlds, I just should play Savage Worlds.
But for the upcoming C&C game I am going to try 2d10 instead of a d20 and see how that works out.

Thanks for all the input.

SavageRobby wrote:
But for the upcoming C&C game I am going to try 2d10 instead of a d20 and see how that works out.

Cool. Are you going with a CB of 12/18 or 12/16? Let us know how it works for you.

-Fizz

Dunno yet, to be honest. Still working that out. I'll probably start BTB, and adjust from there. The group will start as 1st level characters, so we'll have plenty of chances to see if that it too high.