Number three on the list of elements was quicker combats. This is a biggy because combat has steadily slowed across editions and, now, is just crawlin’. There are a lot of ways to make combat quicker and they have consumed a lot of the design focus throughout this project so far. I’m not ready to get into them just yet because a lot is still up in the air, but I do want to discuss some ancillary ways that combat can be sped up. This article is intended to highlight the extent to which the minutiae of game design can impact the play experience.
The big reveal: for the most part, damage expressions should be limited to two dice.
Most damage expressions throughout this homebrew are limited to two dice. Sometimes you’ll roll more because multiple powers are triggered (like sneak attack), but these are the exception rather than the norm. In those cases, the extra time the dice cause is worth it because some exceptional thing is happening. Extra dice are worth the extra time when exceptional events are occurring and I don’t want to get in the way of that. But most things, like routine monster damage, are not exceptional and so are limited to two dice.
The above graph shows two damage expressions with the same average. One is calculated with 4d8+2 and the other with 2d12+7. They both have en expected average damage of 20. Expression A has a range is from 6 to 34 damage and Expression B has a range of 9 to 31. Expression A, then, is interestingly different when the result is 6-8 or 32-34. We like when things are interesting. From here on out, we’ll refer to damage results that Expression A can achieve but B cannot as “interesting.”
Just because they are interesting, however, doesn’t mean they are worthwhile. Only 0.7% of all damage results ever fall into those interesting regions. In other words, if you roll one-thousand damage expressions with 4d8+2, seven of those results would not have been achievable with 2d12+7.
The game table is already home to a lot of stuff. Rolling more dice means you either reroll some dice or you have even more clutter, taking you even longer to find what you need. You also need to mentally add four numbers instead of two, which takes more time and increases the likelihood of errors. But let’s presume that you are quick and the act of finding extra dice, rolling extra dice, and summing extra dice only takes a single second.
The 1000 four-die damage rolls, then, would have taken you 1000 extra seconds or well over two minutes per interesting damage result (1000/7 = 142 seconds). So the question becomes, when one of those interesting damage results arises, does your group spend the next 142 seconds enjoying it? Because that is the cost you’ve already paid by making everyone watch the GM search for, roll, and add the extra dice.
You may rebut that higher dice damage expressions also matter with critical hits. Having more of the expected damage in the variable dice makes a critical hit a much bigger deal. Returning to the examples above, a critical hit with Expression A would deal 4d8+34 damage while Expression B would deal 2d12+31. Expression B can’t simulate damage beyond 55 on a critical while Expression A can reach 66. How often will Expression A result in 56+ damage on a critical hit? About 23% of the time. So 5% of attacks (critical) will result in interesting damage 23% of the time. This is the same as 1.2% of all attacks. Adding critical hits to our analysis above brings our total to 1.9% of attacks or 19 times out of 1000 or ~50 seconds per interesting damage result.
Of course, critical hits are already interesting. Even with tighter expression ranges they do notably more damage and may trigger other powers. The point of this analysis is to determine if the extra time spent to calculate non-interesting damage results is justified by the excitement of interesting results. So if that incremental excitement is lost in the general excitement of the critical hit, we may again want to rethink our design. Moreover, at the same time damage expressions begin creeping beyond two dice, magic weapons are already delivering 3+ of their own. We have plenty of dice to provide a wide range of damage possibilities.
Now consider that for most people, it is probably takes more than a second to find, roll, and add the additional dice. Two or three seconds may even be a modest number, which means we pay multiple minutes for each interesting result.
As 3e evolved, the number of dice and modifiers added to any attack steadily crept up. My last 3e character was an amazingly fun Duskblade who once crit while channeling through his sword and had to roll 25d6 + 3d4 + a host of modifiers from strength, magic, and power attack. It seriously took like 10 minutes (which I enjoyed and no one else at the table really cared). The point is that dice take time to accrue, time to add, and even though they are simple numbers they get all jumbly in your head and make you lose track of other important things. Fourth edition, then, decided to make multiple [w] the heart of the game. There are plenty of opportunities to roll dice and plenty of opportunities to do addition in D&D that don’t add unnecessary time to the game. Moreover, the middle of the turn is the worst time to force someone to lose their train of thought to do a bunch of math.
If you want the turn to go quick, the math in the middle of them has to be simpler. Limiting damage expressions to two dice actually goes a long way towards achieving that and doesn’t have a big impact on play; it just makes it quicker.