A friend and I each run a D&D game, and we also play in each other’s games. We disagree on a number of different things about how the game is best played, and I learn a lot from seeing how both sets of choices play out in each of the two games.

One significant point of disagreement is how important it is to ensure that combat is balanced. In my game I disallow all homebrew and third party content. Only the core rulebooks, and official printed supplements, are permitted. By contrast, my friend has allowed several characters in his game to use homebrew races from the Internet, which are clearly more powerful than the PHB races. And he is quite happy to make modifications to spells and abilities without investigating the consequences for balance. Changes which seem innocuous can have balance consequences that you don’t realise for some time or do not observe without playtesting; I always assume the worst, and don’t change anything. (I constantly reflavour abilities and stats. In this post I’m interested in crunch alone.)

In this post I want to explain why I put such a premium on balance. Before getting on to that explanation, I first need to say something about the blogger Mike Shea’s claim that “D&D 5e is imbalanced by design and that’s ok. Imbalance leads to interesting stories.” (one, two). Shea is drawing a contrast between 4e and 5e. It was possible to more precisely quantify all character and monster abilities in 4e, which meant that if the calculations showed that an encounter would be easy, medium or hard, it was more likely to turn out to be easy, medium or hard. By contrast, 5e involves a number of abilities that can turn the tide of combat suddenly and against the odds. So while the XP thresholds might indicate that a planned encounter will be an easy one, a monster’s ability to petrify a character with just two failed saves could mean that the whole party goes down. Similarly for character abilities that can turn a powerful boss into a sitting duck for the entire combat. Shea points out that such abilities add an awful lot of fun and suspense to the game that might have been lacking from 4e.

I am not in a position to know whether 4e really lacked the kind of surprise and suspense described here. Regardless, Shea has identified something important about 5e. A great deal is added to combat by abilities on both sides that can quickly turn the tide. However, I find it misleading to say that this makes 5e unbalanced. Shea also uses the term ‘unpredictable’, and I think that’s a better way to refer to this phenomenon. For balance is more than determining an accurate challenge rating, and using this to pit the right number of monsters against the right number of players. In the absence of tide-turning abilities, that’s all balance is; however, balance is also a concept that applies to individual abilities, including tide-turning abilities.

I suggest that a very powerful ability, that has the potential to change the tide of a battle, is balanced by some combination of being (i) highly situational; (ii) very resource-depleting; and (iii) requires a saving throw, or similar, with the parameters set so that the full effect of the ability is unlikely to occur. Let me give a few examples. It’s been pointed out that the Fireball spell deals more damage than a multi-target 3rd level spell is meant to deal (DMG, p. 384). However, the spell is highly situational because it is highly likely to also hit your allies. (Evokers have a mitigation for this, but that is at the cost of a full class feature.) Power Word Kill might down a powerful enemy much sooner than expected. But there’s another enemy in the next room, and then that spell slot is gone.

We should conclude that 5e is not imbalanced by design, but unpredictable by design. In fact, I suggest that 5e spells and abilities are a mixture of the predictable and the unpredictable, and the concept of balance applies differently to these two kinds of abilities. A creature’s standard attack is predictable; balancing it is simply a matter of adjusting the to-hit bonus and the damage dice. Balancing its tide-turning ability is a matter of adjusting the factors I discussed in the previous paragraph, and possibly others. Playtesting will be necessary for both of these balancing efforts to succeed. Predictable abilities are unbalanced when they don’t do enough damage often enough, or too much damage too often, as compared with their CR. Unpredictable abilities are unbalanced when they offer systematic ways to change the tide of battle. Indeed, this makes them predictable.

Now that I’ve responded to Shea, I’ll say what I think the point of combat encounters is, and why this leads me to disallow content that has not been rigorously playtested. (My thinking here is very much informed by how Rodrigo Lopez runs D&D on the Critical Hit podcast, and what he says about running D&D in Q&A. Thank you Rodrigo!) Let me first set aside combat encounters that are meant to be a walkover, and combat encounters that are meant to end in multiple deaths or retreat. The purpose of walkover encounters is to set a particular tone in the story. It allows characters to know that certain things are not challenging to them, and this can be built into roleplaying (”we are among the most powerful denizens of the realm. That gives us a certain responsibility.”). The purpose of unwinnable combat encounters is to work through turning points in a campaign’s plot. The fact that an enemy cannot be defeated by the party is likely to drive a whole story arc; actually running that combat, rather than just saying that their attempt to fight the enemy fails, helps drive that home, and gives the characters points of reference (”you saw what happened when he turned his evil gaze upon you, Mazril. We’ve got to find another way!”).

Consider, then, other combat encounters. This is what I think they are all about. The GM creates an encounter that the rules say is winnable, or unwinnable but otherwise surviveable. Then the GM and the players fight out that encounter within the rules, each side trying to fully exploit the resources available to them, though without doing anything that would not make sense from the points of view of the characters and the monsters. Rolls are not made in secret or fudged, and HP totals are not arbitrarily adjusted. The GM does not pull punches. There are no restrictions on tactical thinking; for example, it’s fine for players to deduce enemy ACs, openly discuss them and act accordingly. However, actions taken must have an in-character justification. The outcome of the battle depends on a combination of tactics and luck: unpredictable abilities can turn the tide suddenly, and that might be enough to win or lose, but most of the time good tactical decision-making on the part of the players is rewarded. (The nature of monster abilities means that less interesting tactics are possible; further, the players have multiple brains between them, so ought to be able to out-think the GM in most cases.)

The result is that combat is a kind of minigame within D&D. The GM takes on a different role. In particular, GM fiat is suspended. The rules of the game are in charge (except, of course, where the GM has to make a call about a situation not covered by the rules). But isn’t this to throw out the advantages tabletop roleplaying games have over video games? Isn’t the GM’s freedom to bend the rules what makes D&D more fun and flexible? My basic response is that the rules for combat are only interesting when they do not depend on GM fiat, or other forms of arbitrariness, and for the parts of the game where GM fiat works well, it is better to use ability checks, or skills challenges, or straight roleplaying.

The thought is that the complexity of the combat rules is justified only when those rules are not arbitrary. If the players must think tactically within a system that can change arbitrarily, there’s no longer much point in investing energy in that tactical thinking. It is not intellectually interesting, it is much less fun, and it does not significantly contribute to the story. Tabletop games have an important role for a combination of GM fiat and dice rolls—the chance of those rolls succeeding remaining under the GM’s control—but that can be leveraged with simpler rules than those for combat. Now, I think that the combat rules are fun, so it is good to include them alongside the parts of the game that are more straightforwardly a collaboration between the GM and the players. But they should be deployed differently in order to bring out their strengths.

It should be clear, based on this, why I put such a premium on balance in combat: imbalance introduces arbitrariness to the combat system. If my tactical thinking is nullified by the systematic advantage that another party member has over my character, there’s no point in my engaging in that tactical thinking. Unpredictable abilities nullify tactical thinking in ways that are fun, but only when they are balanced in the ways I described above.

All of this is a matter of degree. I don’t think that combat is fun only when the characters and monsters are restricted to the core rulebooks; I enjoy combat when I play in my friend’s game. My view is just that combat is more fun the less arbitrary it is. I have certainly experienced the sense that my attempt to intellectually engage with the combat is being undermined by certain house rules and the overpowered abilities of homebrew races. Fortunately, thus far this problem has only affected a few turns of combat at a time, rather than whole combats.

Another friend is of the view that the GM should try to convince the players that they really are treating combat as I’ve described, but still fudge dice rolls in order to prevent, e.g., uninteresting character deaths. In response, I’ll note that I don’t feel capable of making those judgements, in the heat of the moment, about whether a death would be interesting. Further, having to worry about this would make combat less fun for me as the GM, and GM fun is important too.