# Aced d4s vs skill development in Savage Worlds

Is there errata covering aced rolls when skills are at low levels vs higher?

I've heard of players staying at rudimentary skill in order to reward themselves with aced rolls more frequently than those with higher dice.

Sorta seems like a game breaker to me.

• They explicitly mention this in the Test Drive; yes, you'll ace more often, but you're acing with a die that will pay less once it does ace. So yes, there is some general distinction, but typically bigger die=higher roll, even with acing involved. While a smaller die may be better for the cases directly beyond itself, larger dice are important to hit higher target numbers with any semblance of accuracy. May 2, 2013 at 17:20

Here is the errata for Savage Worlds Deluxe. There is no mention of changing dice rolls.

In practice, this issue will rarely show up. Consider rolling a d4 or d6 to hit a target number (TN) of 6. The d4 has a slightly better chance of being successful.

d4: 1/4*3/4 = 3/16 or 18.75%
d6: 1/6 = 1/6 or 16.66%


However, skill rolls are only part of the game. Even though increasing fighting from d4 to d6 is slightly worst for a TN of 6, it also provides a +1 parry. There are several edges that require skills of a certain die, forcing you to upgrade them.

Finally, remember that the advantage only holds true for specific TNs. With our d4/d6 example, the d6 is more likely to hit a TN of 8 than the d4 is.

d4: 1/4*1/4 = 1/16 or 6.25%
d6: 1/6*5/6 = 5/36 or 13.88%


And of course, the more sides a die has, the greater the average roll is. As you reach ever increasing TNs (ex: shooting a man with cover from a moving vehicle), higher dice still provide better odds.

Because this problem only applies to very specific TNs (d4/d6 with TN of 6, d6/d8 with TN of 8, etc), I would only compensate for it if your players are trying to abuse it (and the at most 2% advantage they get bugs you). You can easily add 1 to the TN, breaking their strategy without really changing gameplay.

tl;dr The problem you mention is a tiny edge case that has an extremely minimal impact on actual gameplay. A player keeping their skills intentionally low will inevitably regret it as challenges become harder.

It's only a problem if your player characters are Extras (which, by the rules, they're not). That is because your players always roll a Wild Die when testing Traits.

What this means is that If you pick d6 as your skill die, you still get better than with a d4, on all Target Numbers. Your players also forget the importance of Raises in Savage Worlds. That means they should be aiming at getting over 8 most of the time.

Check this graph on AnyDice to see for yourself:

Here's the chance each Wild roll has to succeed against some key TNs, assuming dice exploding up to 4 times. Note that TN 8 = 1 raise above TN 4 and TN 10 = 1 raise above TN 6 - a hard task.

Skill   TN 4    TN 6    TN 8    TN10
d4      85.7%   78.6%   71.4%   64.3%
d6      88.5%   80.8%   76.9%   69.2%
d8      90.3%   83.9%   79.0%   74.2%


Just as a curiosity, using the alternate exploding rule (-1 per ace, as pointed by David Allan Finch and Hand-E-Food) does yield more separation between Skill Dies, with the penalty being lesser absolute numbers.

• I like this graph with the missing numbers is there one with the rest of the dice on. May 3, 2013 at 7:07
• If you click on the links in the answer you'll see it's easy for someone with minimal programming skills to add the missing dice. I can help you with that on chat/PM. May 4, 2013 at 4:43
• Here, have some cake: anydice.com/program/2247/at_least/graph anydice.com/program/2248/at_least/graph May 4, 2013 at 5:02
• The formula in the above graph isn't correct, it isn't calculating the highest of the two dice for Wild Cards. It should look like this: anydice.com/program/31c3/at_least/graph Jan 17, 2014 at 13:46
• That is correct and surprisingly counter-intuitive. Your correct formula yields much lower probabilities than mine. What mine appears to calculate is some magical die that holds all possible outcomes of, say, exploding d4 and exploding d6 and picking one outcome at random. How could this yield higher results than selecting ther higher of the two? Feb 19, 2014 at 2:32

There's nothing official, but there are various house-ruled hacks. Using the standard rules, you can see from the first graph of that post that there are four points where a lower die beats a higher die for at a certain difficulty level.

Given that the Savage Worlds motto is "Fast! Furious! Fun!", it's likely that it isn't worth complicating the rules to handle these edge cases.

• Interesting house rule. I was thinking of a similar one which is "-1 per ace." This makes all subsequent rolls on an exploded d6 be worth from 0 to 5 instead of 1 to 6. That's keeps the larger dice better. Mar 7, 2013 at 6:32

It's not a big difference and certainly not a game breaker. Given most skill rolls target 4, or 8 for a raise, the statistics for each die are:

Die  >= 4    >= 8    >= 12
d4  25.00%   6.25%   1.56%
d6  50.00%  13.89%   2.78%
d8  62.50%  12.50%   7.81%
d10 70.00%  30.00%   9.00%
d12 75.00%  41.67%   8.33%


Going by this table, the only time a smaller die is better is when trying to score a raise, where a d6 outshines a d8. In fact, for all dice, they outshine the next largest die when targetting that die's number. (eg. d4 >= 6 beats d6 >= 6.)

That said, as much of a statistical improbability it is, when a player aces a roll, the die tends to keep on acing. I've regularly seen d4s score well over 20, and d10s over 40.

• "... the die tends to keep on acing"? What? Mar 7, 2013 at 13:37
• I want to vote this up, but I can't rightly with the confirmation bias of the last paragraph. Mar 7, 2013 at 15:49
• There's a lot more than statistics that influences the roll of a die. It could be how they pick it up and roll it. It could be fate! There's a good chance it's just perception. When a die aces once, it's good, but not amazing. When it aces four times in a row, you remember it and it outshines any other roll (except perhaps snake eyes.) Mar 7, 2013 at 22:07
• That last sentence is the definition of confirmation bias. :) Mar 7, 2013 at 22:23
• How is that? It looks to be the complete opposite to me. My answer says statistically there's little-to-no benefit from staying at d4. My last sentance contradicts that with anecdotal evidence. (And at this point, this really deserves to go to chat.) :-) Mar 7, 2013 at 23:47

Yes there is a flaw in the probability, but it is only minor problem in practice. As Hand-E-Food's answer shows it is only a less that one percent error. On opposed rolls where the players have a wild-dice vers a npc without the extra from the wild dice has more of an effect anyway. On static rolls, if an NPC has a parry of say a 6, a skill of d4 is very slightly better than a d6 but in reality you need to get raises to do any real damage and to get the raise of 10 a d6 would be better. So you might get less ordinary hits but you will get more extra damage when you do. The designers claim that it balances out. Seams to from my experience.

If you really want to mitigate this you can get dice with no high number but instead a zero, a d6 for example with 0-5 and roll the ace on the 5. Then add one after the total roll this give the same spread without the theoretical error. I thought about it but could no bring myself to inflict this on my players for such a small error.

Although this issue is very small, some players view it as a deal-breaker, so I think it's worth considering different solutions. A common suggestion is to subtract 1 each time the die explodes, but I find that annoying to remember, and it changes the probability of succeeding at different TNs.

My own preference is to use fudge dice. If you're not familiar with them, fudge dice are d6s with a "+" on two sides, a "-" on two sides, and two blank sides. I treat the "+" as a +1 bonus and the "-" as a -1 penalty, and allow players to roll one or two of them with their trait rolls if they wish.

The nice thing about using fudge dice is that they smooth out the bumps without changing the overall shape of the probability curve - for example, this is a d6. That means if someone forgets to use them, or even chooses not to use them, it doesn't really matter. But if a player is really bothered by the probabilities, it's pretty painless to give them one or two fudge dice and turn this into this or this.

adding modifiers as appropriate such as penalizing characters for being out of thier element or rewarding characters for doing something within thier element. for example, giving a seamstress +2 to her repair roll to sew a fancy dress out of spidersilk because she is trained in sewing as her defined crafting skill. this helps adjust the probability by adjusting the target numbers themselves.

the base target numbers assume there is no modifiers to the dice. and assume you are an extra. wild cards have higher probability, so, adding modifiers appropriate to the character and circumstance affect the probability of achieving target number by altering the result you need to achieve it.

• This doesn’t appear to be answering the question asked. At best it seems vaguely in the neighbourhood of the question, without explaining how it is a solution to the problem. Could you edit this to more clearly explain how it’s relevant to the question? Aug 20, 2018 at 19:41