Designing exciting combat encounters is an important skill for most GM’s. We want to make sure we challenge the party without overwhelming them. In this article, we’ll look at three ways to choose the appropriate number and level of opponents for an encounter. Each has its own advantages and disadvantages.
The Mathematical Method
About the year 2000 (or so) games started incorporating mathematical systems to help with encounter design. Monsters and opponents each have a challenge rating. With a little math you can design an encounter that is appropriate for your players level. This can be done with some precision. You can design easy, medium, or hard encounters using this approach. You can even statistically predict how much of your party’s resources will be depleted in the encounter.
While it offers great precision, there are a few drawbacks. Such an approach takes time that many GM’s may not have. And it can’t guarantee results: some nights the dice don’t behave. The formulae are based on statistics, so the relatively few rolls made in any particular session may not follow these patterns. Lastly, it may train players to expect encounters that are exactly matched to their skills. This may encourage them always to use combat rather than alternatives fleeing or parlaying.
The “Adventuring is Dangerous” Method
Some might call this the old-school approach. In this method, the GM picks whichever monsters or opponents they like, regardless of difficulty. Players are expected to consider each encounter as potentially life threatening. Fleeing, parlaying, and retreating may occur as often as combat. This keeps them guessing, and maybe even a little worried. This method greatly reduces prep time and can allow a GM to design thematic adventures more easily. For example, you could include monsters with a “snake” theme without worrying whether they are perfectly balanced to your party.
However, this can prove quite dangerous for PC’s. This is probably not desirable for new players: you don’t want to kill them their first time out. Some newer players may have trouble adapting to this style of game. They may be used to going toe to toe with every opponent, which could prove deadly. Some GM’s may want these kind of deadly scenarios for their games, but you might need to warn prospective players first. For example, I’ve seen convention games where PC’s die in the first hour of a four hour session. And that’s it. If I were playing in such a session, I’d want to know that up front before committing to that time slot.
The Eyeball Method
This is the “In-between” approach. When planning an encounter, the GM considers the average level of the party, and tries to adjust encounters accordingly. For example, if the opponents are of a lower level than the party, the GM may increase their numbers. If they are of a higher level, he or she may reduce the number of foes. The GM eyeballs it and hopes for the best. This method is much quicker than the Mathematical Method, but can produce a more balanced encounter than the Adventuring is Dangerous Method.
This method is not without limitations. It can still lead to encounters that are either too easy or too difficult for your players. It may not be appropriate for designing published adventures or encounters for tournament play. In those situations, the Mathematical Method may have to be used.
Concluding Thoughts
Obviously these categories don’t encompass all possible approaches to encounter design. Hopefully, however, they do provide some food for thought. And they may not be mutually exclusive. Perhaps you always use the Mathematical Method, but would like to include a very difficult encounter. Then do it. Use the “Adventuring is Dangerous” Method, and perhaps warn your players if they seem to be headed for a total party kill (TPK). If you are losing PC’s left and right, you may need to adopt the Eyeball Method to bring some balance back into play. Your approach may depend on play style and your players’ preference as well.
What approach do you use to adjust the level of your encounters? What thoughts did I miss in this article? Share your thoughts below.
When the encounter difficulty is not matching what I expected I use “Live Eyeballing”. if the players are curbstomping enemies that should be challenging, I can secretly increase the enemies’ hitpoints, or just put more enemies that were “hidden”. If, on the other side, the players seem to be having a really hard time when they shouldn’t, I can make equivalent fudging: reduce enemies’ hitpoints, or make some of them run away, or whatever seems appropriate.
I use this to correct unbehaving dices, or maybe a miscalculation on my part designing the encounter.
I’ve done the same things for years to balance encounters on the fly. Add reinforcement or have planned reinforcements fail to appear. Or fudge a roll: a hit misses or a miss hits.
Another useful approach to adjust encounter difficulty on the fly is to shift the opponents’ tactics to make combat tougher or easier. If the party’s having too easy a go of it, have the monsters fall back to a covered position or establish a flanking attack. If the monsters are crushing the party, have the monsters hold position for a round, or have them foolishly split up into 2 groups (maybe they’re becoming overconfident) that allow the PCs to divide-and-conquer.
I love the term “Live Eyeballing”, wish I had thought of it. And that’s what you sometimes need to do, balance on the fly.
Glad you liked it, fell free to steal it 🙂
@Blackjack: alternating the opponents’ tactics is also a great idea! I guess I already do it sometimes, but not very conscious of what I’m doing. I will add to my list of strategies of Live Eyeballing.
I usually avoid dice fudging: if you already know the outcome you want, why roll? That’s why I roll on the open, so even if I wanted to fudge, I “can’t”. I prefer to make misses create a new situation, like knocking something over altering the battlefield.
The mathematical method also makes assumptions about what party composition is. Midrange undead might not be very scarey to a party with a cleric and wizard, but they could easy destroy a party who have a druid and a bard in those roles instead.
Right, I had forgotten to consider party makeup in the CR formula. We didn’t have a magic user for a while and they we hurting.
Well anybody who knows the CR system also knows that it isn’t as precise as its touted to be, though I still use it as my primary method of creating balanced encounters. That said, I almost never place PCs on equal footing with an encounter, most often the encounter monsters are CR+2. I only use equivalent CR as a build up encounter towards the final one. Final encounters of every session are always at least CR+2 over the PCs. My players are pretty savvy and tactically advantageous in most encounters, so equal CR is never truly equal – PCs tend to be stronger than that.
I find it usually isn’t too hard to observe your players and adjust the challenge of this encounter or the next one based on their reaction. The emotional response to the challenge is actually more important than the math in my opinion. A lousy group of goblins can be more terrifying than a dragon if you focus on the narrative.
And if you am not sure or am using a new system, I go for an easy encounter first (to make the players feel cool and mighty) and then increment the difficulty as the session progresses.
Communicating expectations is key. Much like traps, different games have different expectations.
If you played 4th edition encounters, the foes were described as tough, verging on unbeatable… but the evening’s adventure was to win that “unbeatable” fight. If you throw a similarly described foe in 1e or 5e, that player’s going to assume that it’s over the top description, like they’re used to… and be disappointed when their defeat is preordained.
That conflict is actually a big issue in the first chapter of Hoard of the Dragon Queen. There’s a terrifying blue dragon and troops burning a town. Are the PCs expected to fight the dragon? Communicating expectations (and a lot of foreshadowing, or OOC hinting) is the only way to make the confrontation satisfying.
Sometimes the players better balance the encounter, by retreating themselves outta there!
If folks know when to run, the DM doesn’t have to do much balancing at all.
But as Scott said, if expectations aren’t on the same page, no one is going to think about running. Also, in most tabletop RPGs, running is basically just suicide for at least some of the party unless the enemy decides to let them go. As a result, throwing in encounters where the party “should” run can feel like the GM is just being a ^%$^%&% because there really wasn’t any way to get away either.
Communicating expectations is key. Much like traps, different games (or even editions of the same game) make different assumptions.
If you played 4th edition encounters, the foes were described as tough, verging on unbeatable… but the evening’s adventure was to win that “unbeatable” fight. If you throw a similarly described foe in 1e or 5e, that player’s going to assume that it’s over the top description, like they’re used to… and be disappointed when their defeat is preordained.
That conflict is actually a big issue in the first chapter of Hoard of the Dragon Queen. There’s a terrifying blue dragon and troops burning a town. Are the PCs expected to fight the dragon? Communicating expectations (and a lot of foreshadowing, or OOC communication) is the only way to make the confrontation satisfying.
I’ve always been an old school DM. Always change modules to fit your groups make up. My main 3.5E D&D group runs from stuff all the time! Lots of running fights. We’ve had lots of encounters where they see the number of enemies and start saying “Maybe we should run? Let’s give it a round or two and see how it’s going first.” It’s worked so far, they are the highest level party I’ve had since DarkSun 2E!
Breaking up the encounter into ‘waves’ allows you to not TPK with a -2 or -3 foe. It also allows you to counter some of the trick tactics cocky players develop. If the first wave turns out to be tough, the others can be thinned or ‘faked’. In a recent game, a goblin crew used rattling cans to distract to party’s rear rank. One sneaky goblin is a lot different from another dozen pointy bits of metal.