One question I often come across in various Dungeons and Dragons conversations is “How do I balance my combat encounters?” It’s far from a bad question, but reading through the various responses, it seems that it only scratches the surface of its intent. Based on the answers, there seems to be this assumption that a “balanced” encounter somehow guarantees a “fun” encounter, that if an enemy’s statistics are perfectly calculated, the party will be engaged and energized. Now I’m not at all saying that game balance is irrelevant to this topic, but oftentimes it's treated as if it's the only component worth talking about. So, if game balance is only one piece of the puzzle, what are other tools we can use to build combat encounters that reward players for their engagement?
Tool #1: Game Balance and Setting Values
Game Balance is a term that gets thrown around a lot in DMing circles, but do we know what it actually means? To keep myself accountable, I went to the most reliable information source I had: Wikipedia. Wikipedia defines game balance as a “part of game design (that) can be described as a mathematical-algorithmic model of a game’s numbers, game mechanics, and relations between those. Therefore, game balancing consists in adjusting those to create the intended experiences, usually positive ones.” And although we can debate the legitimacy of Wikipedia as a reputable source, I do agree with this definition.
The key takeaway from this is that the reason we’re adjusting game statistics is to create an “intended experience”. The game system’s numbers are set so that they give players a certain feeling when they discover them. To do this effectively with a creature stat block you tend to run in combat, you have to consider your player characters’ statistics when setting them. The only real meaning to quantities in Dungeons and Dragons is to compare them to each other. It doesn’t matter if a player character has a Strength of 20 or 40, as long as it’s in proportion to what that character should feel like compared to a commoner. If a player character has a Strength of 40, and a commoner has a Strength of 35, your player character won’t feel as exceptional.
So let’s take a look at some values we can set for our creatures, and the impact they have on the experience we intend to deliver.
Armor Class and Attack Bonus
Armor Class (AC) determines how often your creature gets hit, and will largely inform your players if Attack Rolls or Saving Throws are more reliable to use. Do note that Martial Classes rely on Attack Rolls to hit, so if you create a creature with a virtually prohibitive AC, you may invalidate the efforts of at least half of the available character classes in the game. This is fine for presenting a creature the party isn’t intended to fight, but it can be soul-crushing when the party fighter feels completely ineffective because they are excluded from participating in the fight due to statistics.
When I set a creature’s AC, I first look at my players’ average Attack Bonus. For example, in my latest game, my players were all 5th level, meaning they have a proficiency bonus of +3. If they didn’t intentionally misbuild their characters, their primary stat is probably a +3 or +4, meaning that they have an average attack bonus of +6 or +7. Therefore, if I have a creature with an AC of 17, they’ll have to roll at least a 10 or 11 on the d20 to hit, meaning they have a 50-55% chance to hit my creature. If I increase the AC any higher, that chance decreases even more. I find that when players have a 40% chance or lower to hit a creature, they’ll feel as if they’re not meant to hit it. Although we can justify the reasoning why a creature may have an AC of 18 or 19, is that reasoning more important than giving your players the excitement of hitting and dealing damage?
Of course, as with anything in TTRPGs, there are exceptions. One factor I consider when designing the environment of the encounter is how easy it is for my players to get advantage on their attack rolls. Advantage accounts for an average of an additional +5 to their attack rolls, meaning characters with a set attack bonus of +6 or +7 are now functionally rolling with a +11 or +12, and they have a greater chance to land a critical hit. If I set up an encounter where it's easy to flank, or I know one of my players brought a Druid or Mastermind Rogue that has features or spells that grant their allies advantage, I have to rethink my math. Maybe an AC of 19 or 20, especially if I’m overt about the strategic clues my players can leverage to make the most out of each of their attacks. To reiterate, this is a mechanical approach in order to deliver an intended experience that is justified with description and story afterward.
One last piece of feedback I’ve taken to heart (in terms of Armor Class) was from one of my long time players and friends. “It always feels better to have a creature with a lower AC and more Hit Points because then at least I feel like I’m doing something.”
Now the flip side to Armor Class is the Attack Bonus, the modifier that’s added to an attack roll to determine if you hit a creature’s Armor Class. Just like I calculate my creature’s AC based off of my player’s attack bonuses, I also take their AC into account when designing my creature’s attack bonus. For example, if I know one my players have an AC of 14, a +8 attack bonus means my creature has to roll a 6 or higher on the d20 to hit. Add on multiple attacks, and they are hitting far more often than they miss.
Now that same +8 to hit the tanky fighter with an 18 AC? The creature has to roll a 10 or higher, meaning they have a 55% hit rate against that character. But is that the feeling I want my fighter to have? Do I want the party fighter to get hit more than half of the time? My answer, as always, is that it depends. Sometimes I do, sometimes I don’t. If the party is fighting a single, tough monster like a troll or otyugh, then maybe the fighter takes some hits for the sake of the party. If the party is fighting a bandit captain and his goons, maybe I want the party fighter to feel a little unhittable and get excited by the fact that the goons aren’t able to make it past their masterful defense. After all, if they built their character with a high armor class, don’t we want to reward them with an encounter where they feel like they have a high armor class?
So to summarize this one quickly, first I look at the party’s average AC. The number of attacks matters here. Two attacks with a +8 modifier is a different game than one attack with +9. Remember, if a creature gets two attacks, both with +8, it's almost like they’re rolling with advantage (so really it's like one attack with a +13) with the difference being that if they roll high on both attacks, the damage is essentially doubled. In Fifth Edition’s simple math, a one point change in Attack Bonus or Armor Class can lead to a huge gap in probability, and adding or subtracting attacks or actions will quickly widen that gap further.
HP and Damage Output
Hit points are a measurement of progress in a fight, and I actually find that the average hit points presented in the Monster Manual cause combat to get over with a little too quickly. However, maxing out a creature’s potential hit points is a great way to create tension in a combat encounter. Remember that game statistics are used for reference. If your 5th level Barbarian has sixty something hit points, and the thing their fighting has 240, how will your Barbarian feel in comparison?
Also remember that you as the DM are at liberty to change a creature’s hit points on the fly (a contentious opinion, but my opinion nonetheless). For example, I remember a one shot I participated in where we were introducing a brand new player to Dungeons and Dragons. We were all 4th level, and were fighting a young green dragon as an end boss. The new player, a Paladin, had used a potion of flying, which the DM described as giving him two luminescent angel wings. On his next turn, just as the dragon’s breath weapon knocked out my druid (the healer) and the sorcerer (our primary damage dealer up until that point), the paladin catapulted toward the dragon, hit with a Natural 20, used Divine Smite, and slayed the beast. After the game, the DM admitted to me in a private message that really, the dragon would have had 1 hit point left, but what made for a better story? The paladin (again, played by a NEW player) charging forward with heavenly wings and smiting with the wrath of Celestia? Or the ranger shooting another mundane arrow. When there’s an epic moment that can generate a memorable finish to a fight, why does the last hit point matter?
My final piece of advice on hit points is to include more resistances and vulnerabilities to your creatures. I took this from Zee Bashew’s Making Enemies in 5e Witchery (link https://www.youtube.com/watch?v=GhjkPv4qo5w&t=46s), and it’s only made my combats more exciting since. One of our goals in crafting exciting encounters is to reward players with engagement, meaning they’re paying attention to story clues that can help them strategize in combat. I can’t count the number of times a DM has given a lengthy and vivid description of their monster, and when I went to act on that description to give me an edge in combat, they’re response is “Well, that was for flavor. There are no mechanics to take advantage of”. To me, they might have well have said “Thank you for listening to my lengthy description. It doesn’t actually matter if you did or not. I’m just using it to justify a bunch of custom mechanics to make your life more difficult”. And I’m not picking on one person. I’ve played with a lot of different DMs, and this has come up time and time again.
Rather, wouldn’t it reward engagement if it did matter? For example, if I said, “The aboleth’s skin glistens with a slimy coat of mucus as it cranes its body over the party”, and a player said, “Slimy? If I use a cold spell, will it restrict its movement?”, I may double movement penalties caused by a ray of frost, or give it disadvantage on a Constitution save against cone of cold. If my players are engaged with my descriptions, shouldn’t I reward them for that (even if I didn’t think of it during prep)? Even better, I may have cold damage deal double to this aboleth because of their logic. By offering different creatures with different vulnerabilities, it encourages players to try different spells and damage types in order to discover what works best against each kind of enemy. And, even though they’re dealing double damage, the creature’s hit points are maxed anyways so the rhythm of the fight isn’t really disrupted.
Resistances also give the players new information. If you present a creature with a resistance (that makes sense given its lore), then players may find that their go-to damage choice isn’t working, and encourages players to prepare two or more options of damage types to switch between. This way, a player doesn’t go through multiple combats relying on a single choice, then feeling as if an encounter was designed against them because their only prepared option doesn’t work. One thing to note on vulnerabilities and resistances: I almost never use them for physical damage (bludgeoning, piercing, slashing). If a creature is resistant in this way, it's to non-magical attacks. Most martial characters are built with a single weapon specialty in mind, and often only have one weapon damage type as their only option. When a DM enforces carry weight and variant encumbrance (like I do), it also complicates matters. Fifth Edition rewards casting characters much more than martial characters as is, so reducing the complications of feeling successful as a martial character improves the health of the party’s relationships.
As for damage output, I find that many times the default monster actions tend to do a great job at conveying how hard a creature can hit. If anything, I may increase or decrease the damage die by one size (like making a 2d6 attack 2d8), but I find that the number of attacks or actions is a much more relevant value to adjust rather than the damage it hits for. Like I said before, two attacks with a +8 attack bonus can be much more deadly than one attack with a +9, and understanding how much damage a creature is likely to output has to do with its action economy (more on that later).
Saving Throw Bonuses and Spell Save DC
It makes sense that each creature would have natural defenses against certain kinds of attacks, and that they should have greater saving throw bonuses to match. Like with vulnerabilities and resistances, the key to creating an exciting encounter is to give the enemy creature a discoverable weakness the players can leverage into their strategy. Also, as said before, those high and low saving throws should be based on context clues you include in your description, encouraging your players to remain engaged with the details you give them. A spindly creature with spider-like movements may have a high Dexterity save, but hitting them with a Wisdom saving spell may have a higher chance to succeed. A calculating enemy wizard may have studied how to protect their mind, but requiring them to succeed Dexterity saves may be more difficult for them.
Now each creature in Fifth Edition has a Saving Throw bonus to each of its main six abilities. However, three of them are more common than the rest, and these are the ones that matter in terms of game balance: Dexterity, Constitution, and Wisdom. When designing an encounter I usually have one of these saves be higher and one be lower, or keep all of them at relatively neutral values. Like how we set AC in relation to the party’s average Attack Bonus, taking their Spell Save DC into account. A +7 bonus to a Saving Throw might not sound like much, but if a player’s Spell Save DC is only 13, then it’s more likely than not your creature will succeed its save, and the player may not feel that spell is effective.
One counter example I’ve heard is that “old monsters are old for a reason”, and that they would have developed natural defenses to these common kinds of attacks. The logic does track. An ancient dragon is ancient because it figured out how to withstand Dexterity saves, is tough enough to handle a Constitution save, and may be wily enough to avoid a Wisdom save. However, if a creature has no weakness, it's just as boring as an encounter where everything always works.
This is where I like to employ conditional weaknesses. For example, let’s say the party is fighting an ancient red dragon. The dragon has decent saves across the board, and its immunity to fire damage and resistance to cold (at least, my dragon) is proving to be a challenge. However, when the dragon tries to fly, one of my players (who played Pokémon) decides to try to hit it with a call lightning spell. While the dragon isn’t vulnerable to lightning damage, it does have disadvantage on saving throws against lightning while it’s flying. By creating a condition that reveals the creature’s weakness, it encourages the party to strategize to solve the puzzle of the combat.
The last piece of this puzzle is legendary resistances, a mechanic I despise because it’s never been used to create excitement. Because legendary resistances are only used after the DM knows that the monster’s saving throw has failed, they retroactively rewrite a player’s success by design, which can leave a player feeling that their choice was meaningless. Now this doesn’t mean I don’t use legendary resistances at all, but the form they take is definitely adjusted from the by-the-book approach.
And like each of these sections, the flip side of calculating my creature’s Saving Throw bonuses is their Spell Save DC (or just DCs for whatever nasty effect they may have up their sleeves). However, unless the creature’s main abilities will revolve around the Spell Save DC rather than Attack Rolls, I’ll try to keep the Spell Save DC a little lower (usually between 13 and 15). The reason for this is that I usually tinker with my monsters’ action economy to balance out certain effects against the party, meaning they can spam Saving Throw features that inflict conditions that can really hamper the party. Because party members are more likely to have to make these saves, to me it creates a better flow to have them succeed slightly more than they fail. If that Save DC is too high, my players can be overwhelmed easily. Like I said before though, if the party is facing off against a dedicated caster whose whole schtick is using Saving Throw spells, then the Spell Save DC will be a little higher (probably a 17 or 18), although I usually design some kind of other flaw into their Stat Block that the party can take advantage of.
In summary of this tool, keep your players’ stats in mind while setting or adjusting the stats for the creatures you want to run. If you don’t know your players’ stats, build a quick character at their level and see what stats you’d generate. It’ll give you a pretty good idea of what numbers to work with to create an exciting experience. Just remember, little changes make a big difference, and even a one point change can be the difference between an exciting battle, a frustrating one, or worse yet a boring one.
Tool #2: Action Economy
One resource that fundamentally changed the way I look at running enemy creatures was Matt Coleville’s Action Oriented Monsters video (link https://www.youtube.com/watch?v=y_zl8WWaSyI&t=1282s), which posits that giving monsters a full action economy can change the dynamic between player characters and their foes. Most creatures don’t get a bonus action or reaction in the same way that PCs with Class Levels get. If you break down a standard action economy, a single big creature gets one turn for every four turns that an enemy party gets, which means the player character party gets to hit four times as many times as the one big monster. While this might be balanced by just giving the one big monster higher stats, like we determined earlier, four times as many actions is a very different economy then two bigger attacks.
Now there is a little bit of divergence I’ve taken from Coleville’s approach. Coleville grants his monsters extra actions that coincide with the same language as the players. Oftentimes, I ignore this mechanical language to bring my players’ attention to the action at hand, both in description and in function. Rather than have my creatures choose between casting a spell or attacking twice, I let them do both. Why? I’m the DM, I say so, and it creates more exciting encounters. Not only do my solo monsters deal damage, they usually have an additional condition-inflicting effect that can change the circumstances of the encounter. It’s one thing to know that the giant we’re fighting deals a nasty amount of damage. It’s another when they can swing twice, then use a third action to attempt to knock another creature prone with a Dexterity save. This may change the party’s strategy and position, and the team may have to pivot rolls to best deal with this threat.
Of course, another simple solution is to just add more pieces to the board you control. While I think this may ultimately slow down play (as the DM has to now remember the actions and features of more than one creature), it can work to divide the party’s attention between multiple threats and give them more targeting choices than just the one big monster.
My favorite approach lies somewhere in the middle. Have one big monster with usually two attacks and some kind of spell/condition effect, then give them a bunch of minions to annoy the party. The more variables you add to the encounter, the more chances your players have to utilize situational spells and create memorable moments.
Tool #3: Changing Circumstances
This is a term I’ve used a bit throughout this post, but it does ring true. When we talk about dynamic combat, we’re literally talking about combat that changes and progresses. Oftentimes, high level encounters amount to facing enemies with a bevy of defenses and immunities, which encourages players to choose reliable damage dealing options because there’s virtually no chance for success.
Remember how I mentioned I hate Legendary Resistances? Well this final tool is what’s turned my combat encounters from predictable, stale damage slogs into dynamic and engaging puzzles. Circumstances change as the battles progress. By including puzzle pieces like damage vulnerabilities and resistances, players at my table know that by trying different options, there is new information to discover. Newly discovered information is a change to the battle’s structure. I’m also not above changing those static values we mentioned earlier due to logical happenstance. For example, if I present a stone golem with a high AC, but a caster uses an acid spell (a damage type that’s often ignored because of its lower damage output), then often I reason that the acid erodes the golem’s tough armor, and maybe even lowers its AC, making it easier for the martial characters to hit. And those legendary resistances? Each time my players deplete a creature’s hit points past certain thresholds, my legendary monsters lose their legendary resistances accordingly. Legendary resistances prevent legendary monsters from being defeated instantly due to a bad roll against a feeblemind or eyebite spell, but having those spells never work is just as boring. So by relegating those spells toward the end of the fight, it encourages my players to save their best spells for when the legendary monster is tired and hurt, and as such can’t use legendary resistances even if they haven’t used one all fight. I distinctly remember the collective cheer at the table when my player’s lowered by ancient dragon’s hit points below 25% maximum, and I told them it meant that there were no more legendary resistances left. It’s a celebratory moment that opens the possibilities to more dramatic endings to epic set piece encounters.
My last point for this section is that you can let your players know their choice mattered through mechanical change. For example, if your players are interested in having their social interaction mid-combat affect the enemy’s behavior, have your enemy choose their targets differently. If your player has a clever description or idea, introducing game elements that can get in the way of it succeeding discourages your player from pursuing such ideas in the future. Whether a certain line of thinking excites you or not, remember that how you rule situations mechanically determines the storytelling potential you allow for at your table. And there is nothing wrong with saying “No”.
There were a few tools within tools I mentioned here, and all of this may be overwhelming to take in at first. Do note that while this is a fairly comprehensive list of the factors I take into account when designing my encounters, this was by no means learned overnight. It was years of running encounter after encounter, including small changes over time that lead to this. Hopefully you’ve found something useful in these notes, and you might even find yourself coming back to them to slowly integrate different elements. The overarching theme is to pay attention to what energizes your players. I’ve run encounters of simple goblins with no real strategy and had my players have a blast, and I’ve run more complex encounters with players feeling like it wasn’t fair. Use what works for you and leave the rest. This is just what’s worked for me, and as I learn more, I’ll be sure to share that with you as well.
Study Hard, Play Hard
Professional Game Master musician, music teacher, game designer, amateur bartender, and aspiring fiction author.
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