Rules Index | GM Screen | Player's Guide

Chapter 2: Building Games

Encounter Design

Source GM Core pg. 75
Encounters play a fundamental part in roleplaying games, but it can be tricky to know where to start when building them. It's important to follow the rules and guidelines, but creating a compelling encounter goes beyond that. Good encounters have a place in the story, compelling adversaries, interesting locations, and twists and turns to make them dynamic.

Encounter design goes hand in hand with location, map, and adventure design. You might set an adventure in a swamp and populate it with swamp creatures and environmental features. Or you might have a dungeon denizen in mind, and structure a section of your dungeon to fit that creature.

When you're starting out, straightforward encounters of low or moderate threat can let you get your bearings. Then, you can increase complexity as you get more confident and as the PCs collect more tools to use against their foes. The more encounters you build, the more comfortable you'll get with your own personal style. You can always come back here to get more ideas or advice on executing a certain type of encounter.

Combat Threats

Source GM Core pg. 75
The most common type of encounter is a combat encounter, where the PCs face other creatures. Combat encounters are strictly governed by rules; the guidelines that follow will help you build combat encounters that pose appropriate challenges for your group. Building hazard encounters works the same way.

To build a combat encounter, first decide how the encounter fits in the adventure as a whole. Then, estimate how much of a threat you want the encounter to pose, using one of five categories below.

Trivial-threat encounters are so easy that the characters have essentially no chance of losing. They're unlikely to spend significant resources unless they're particularly wasteful. These encounters work best as warm-ups, palate cleansers, or reminders of how awesome the characters are. A trivial-threat encounter can still be fun to play, so don't ignore them just because of the lack of challenge. Low-threat encounters present a veneer of difficulty and typically use some of the party's resources. However, it would be rare or the result of very poor tactics for the entire party to be seriously endangered.

Moderate-threat encounters are a serious challenge to the characters, though unlikely to overpower them completely. Characters usually need to use sound tactics and manage their resources wisely to come out of a moderate-threat encounter ready to continue on and face a harder challenge without resting.

Severe-threat encounters are the hardest encounters most groups of characters have a good chance to defeat. These encounters are appropriate for important moments in your story, such as confronting a final boss. Use severe encounters carefully—there's a good chance a character could die, and a small chance the whole group could. Bad luck, poor tactics, or a lack of resources can easily turn a severe-threat encounter against the characters, and a wise group keeps the option to disengage open.

Extreme-threat encounters are so dangerous that they are likely to be an even match for the characters, particularly if the characters are low on resources. This makes them too challenging for most uses! Use an extreme encounter only if you're willing to take the chance the entire party will die. An extreme-threat encounter might be appropriate for a fully rested group of characters that can go all-out, for the climactic encounter at the end of an entire campaign, or for a group of veteran players using advanced tactics and teamwork.

XP Budget

Source GM Core pg. 75
Once you’ve selected a threat level, it’s time to build the encounter. You have an XP budget based on the threat, and each creature costs some of that budget. Start with the monsters or NPCs that are most important to the encounter, then decide how you want to use the rest of your XP budget. Many encounters won’t match the XP budget exactly, but they should come close. The XP budget is based on a group of four characters. If your group is larger or smaller, see Different Party Sizes on page 76.

Table 10-1: Encounter Budget

ThreatXP BudgetCharacter Adjustment
Trivial40 or less10 or less

Choosing Creatures

Source GM Core pg. 76
In all but the most unusual circumstances, you'll select creatures for your encounter that range from 4 levels lower than the PCs' level to 4 levels higher (see the Creature XP and Role table). Each creature has a part to play in your encounter, from a lowly lackey to a boss so mighty it could defeat the entire party single-handedly.

Each creature costs some of the XP from your XP budget for the encounter, based on its level compared to the levels of the characters in your party. For instance, if the PCs are 5th level, a 2nd-level creature is a “party level – 3” creature, a lackey appropriate for a low- to-moderatethreat encounter, and it costs 15 XP in an encounter's XP budget. Party level is typically equal to the level of all the characters in the party (find more detail on page 57).

Table 10-2: Creature XP and Role

Creature LevelXPSuggested Role
Party Level -410Low-threat lackey
Party Level -315Low- or moderate-threat lackey
Party Level -220Any lackey or standard creature
Party Level -130Any standard creature
Party Level40Any standard creature or low-threat boss
Party Level +160Low- or moderate-threat boss
Party Level +280Moderate- or severe-threat boss
Party Level +3120Severe- or extreme-threat boss
Party Level +4160Extreme-threat solo boss

Different Party Sizes

Source GM Core pg. 76
For each additional character in the party beyond the fourth, increase your XP budget by the amount shown in the Character Adjustment value for your encounter on the Encounter Budget table. If you have fewer than four characters, use the same process in reverse: for each missing character, remove that amount of XP from your XP budget. Note that if you adjust your XP budget to account for party size, the XP awards for the encounter don't change—you'll always award the amount of XP listed for a group of four characters.

It's best to use the XP increase from more characters to add more enemies or hazards, and the XP decrease from fewer characters to subtract enemies and hazards, rather than making one enemy tougher or weaker. Encounters are typically more satisfying if the number of enemy creatures is fairly close to the number of player characters.


Source GM Core pg. 76
Variety in encounters is essential to let players try new tactics and give different PCs chances to shine as they face foes with weak points they're uniquely suited to exploiting. Consider the following forms of encounter variety.
  • Theme: Look for ways to include varied creatures and locations. Even if the PCs delve into a dungeon inhabited by undead, they should encounter other creatures, too! All creatures should have a justification for fitting in, but no place needs to be uniform.
  • Difficulty: A string of moderate-threat encounters can feel flat. Use low- and even trivial-threat encounters to give PCs chances to really shine, and severe-threat encounters for especially powerful enemies. Extreme-threat encounters should be used sparingly, for enemies who match the threat posed by the PCs and have a solid chance of beating them! The adventure recipes on page 68 include a mix of combat difficulties that can be useful to look at.
  • Complexity: Use high complexity judiciously, saving it for important or memorable fights.
  • Encounter Composition: The number of creatures per encounter and their levels should vary. Higherlevel single enemies, squads of enemies, and large numbers of lackeys all feel different.
  • Setup: Not all encounters should start and end the same way. PCs might sneak up on unprepared enemies, get ambushed by foes hunting them, enter into a formal duel, or find a diplomatic overture fails and turns into a fight. On the other side, enemies might all be taken out, retreat, beg for mercy, or even shift the encounter to a chase or other phase.
  • Information: Uncertainty can increase the tension and sense of danger the players feel. Ambushes, fights against unknown foes or foes behind battlements, and other scenarios can create this basic uncertainty.

Encounter Locations

Source GM Core pg. 76
Choose compelling settings for your encounters. When encounters take place in a building or lair, the most significant environmental features originate from the occupants, both past and present. Think about their tastes, biology, or wealth. These features could be natural, such as the sickening reek of decay in the lair of a great predator. They could also be alchemical, such as a cloud of poisonous gas, or magical, such as a strange electric current that arcs through the walls and occasionally leaps out at passersby.

In some cases, you'll have a location in which an enemy always appears, and you can design your location to suit that specific creature. Other times, an encounter might appear in a variety of places, such as a guard patrol or wandering monster. In these cases, you'll need several terrain and structure options so there's something interesting about the environment no matter where the battle takes place.

Maps and Terrain

Source GM Core pg. 76
Features on the map have a substantial impact on the flow of combat. Three considerations to keep in mind when designing a map are maneuverability, line of sight, and attack ranges. Even empty rooms and corridors can provide variety based on their size and shape. Narrow passageways make natural choke points. In particularly small rooms, space is at a premium, favoring melee combatants and making area effects hard to aim without friendly fire. By contrast, huge areas lend themselves to spread-out combat, which gives plenty of room to use all manner of abilities but poses challenges for ones with limited range. To make large rooms more interesting, add furniture, stalagmites, or other features the PCs and their foes can duck behind for cover.

Inhabitant or Intruder?

Source GM Core pg. 77
In most cases, the PCs enter territory that's far more familiar to their foes than it is to them. NPCs and monsters who live in an area are likely to be adapted to its dangers, either because they know where they are and how to avoid them, or because they are unaffected by them. A kobold in their lair might bait a PC into walking into a trap the kobold avoided. Marshland may be troublesome terrain for most PCs, but it poses little inconvenience to amphibious creatures. When using creatures with the ability to burrow, climb, or swim, consider incorporating features such as mazelike corridors, high walls with platforms, or rivers. If the foes are smaller or larger than the PCs, consider including paths, cubbyholes, staircases, or narrow passages that one side of the fight can use more effectively.

Sometimes, though, the PCs must defend their own base from intruders. In these situations, you're flipping the script, so give the PCs time to trap and ward the area. Watching the invaders fall prey to hazards and ambushes can be a delightful change of pace for your players.

Wild Weather

Source GM Core pg. 77
On a bright, sunny day, the PCs see clearly and fight without obstruction, but adding wind, precipitation, or fog creates additional challenges. Rain creates sloshy, muddy ground that slows movement, and cold weather introduces the threat of slippery patches of ice. Only the most extreme temperatures have a direct impact on the PCs during an encounter, but a slog through blistering heat or freezing cold can leave the PCs worn out and more vulnerable to foes. Light levels play a key role in both outdoor and indoor encounters. Although torches are plentiful, their reach is limited, and lights are sure to draw attention in dark areas.

Budgeting for Terrain

Source GM Core pg. 77
If you include terrain that’s tricky to navigate or takes extra work to deal with, consider whether it should count toward the encounter’s XP budget. A fight that requires Climbing, Swimming, or pushing through difficult terrain can be much tougher—especially if the enemies have strong ranged attacks. Think about the impact of the terrain in advance, especially if the battle would already be a severe threat, or you might kill the party. You can pick an equivalent monster level for your terrain and factor that into your budget, or just assign extra XP at the end if the threat without terrain is on the low or moderate end.

Enemy Motivations

Source GM Core pg. 78
Every encounter should happen for a reason. Consider a creature’s motivation to fight. Is it defending its lair? Robbing to enrich itself? Following sadistic impulses? Simply being paid to fight? You may realize a creature doesn’t have a compelling motivation, or that the PCs have done something that eliminates the impetus to fight. In that case, the encounter doesn’t need to happen! Your game might be more satisfying if the PCs’ clever actions avoid the fight—provided you award them XP accordingly.


Source GM Core pg. 78
Think how an enemy reacts when a fight is going poorly for them—or well! Enemies who do something other than fight to the death make an encounter more dynamic and believable. While PCs occasionally encounter truly fanatical zealots or single-minded creatures that would never back down from a fight, most creatures—even nonsapient creatures like animals—back down from a battle they’re obviously losing. This normally means foes fleeing at a certain point, potentially ending the encounter, but if the PCs need to capture those opponents, it could add a secondary objective and split their focus. Look at how differences in morale between participants impact the fight. For instance, after the necromancer’s living allies surrender to the PCs, she might activate a latent magic she implanted within them, killing them and merging their bodies into an enormous undead abomination. An enemy’s morale could even change the encounter from combat to social, as the PCs enter negotiations over a surrender or try to convince foes of the errors of their ways.

Dynamic Encounters

Source GM Core pg. 78
While you can certainly create enjoyable encounters by placing a group of opponents in a square room with little else, you have numerous tools to create encounters that are more interactive and dynamic. These tools can challenge your players to invent new strategies, inspire interesting character decisions, and make your setting richer.

No encounter needs to use all of the elements presented here, and not all encounters need more than one or two. The more complex a dynamic encounter is, the longer it takes to run and the more demanding it is. In general, these tools are perfectly suited for boss encounters, for memorable foes, and as a spice to add throughout your campaign however often works best for you and your players.

Hazards in Combat

Source GM Core pg. 78
In isolated encounters where the PCs have plenty of time to recover from hazards' effects, simple hazards can feel more like speed bumps than true challenges. But when combined with other threats, even simple hazards can prove perilous. A noisy explosion can draw attention, allowing foes to burst through the door for a dramatic start to the encounter. Simple hazards can also be an active part of an encounter, particularly if the foes know how to avoid triggering them.

As their name suggests, complex hazards are a more powerful tool for encounters. Because they continue to act, they are an ongoing presence in the fight. When combined with hostile creatures, complex hazards offer the PCs plenty of choices for what they want to do next. This is particularly true if foes benefit from the hazard. Should the PCs first disable the array of pipes spewing magical fire into the room, or should they prioritize the fire elemental growing stronger with exposure to the inferno? There's no right answer, and the PCs' choices have a clear impact on the obstacles they face. Hazards in combat shine when they give the PCs ways to contribute meaningfully other than dealing damage to a creature. Interesting actions to disable a hazard are a fun way to give several PCs something fresh and different to do rather than piling on damage.

Evolving Battlefields

Source GM Core pg. 78
While some battlefields are relatively static, allowing the PCs and foes to clobber each other until one side wins, complex or evolving battlefields can lead to far more memorable encounters. One of the most straightforward ways to create an evolving battlefield is with dynamic environmental features. Maybe the floating platforms that make up the room's floor shuffle around on their own turn each round, or various points teleport creatures to different locations—possibly between two rooms where separate battles take place simultaneously. These dynamic features have some overlap with complex hazards, though they don't tend to be an opposition or obstacle specifically threatening the PCs.

Similarly, a third party in the encounter, perhaps a rampaging monster or a restless spirit, could pose a danger to both sides but potentially benefit either. For instance, perhaps the PCs or their foes could harness this third party as a dangerous but powerful ally with a successful skill check of some kind or by making a risky bargain.

Sometimes the evolving battlefield is more of a state change, or series of state changes, and less of a constant presence. For instance, defeating a ritualist and ending his ritual could cause the foes to lose a powerful beneficial effect but unleash a demon that crawled through the remains of the botched ritual, or cause part of the room to collapse from the magical backlash. Major physical changes to the environment, like such a collapse, portions of the room rising or falling, or water beginning to rush in and fill the room, can force the PCs to rethink their plans to handle the new situation. Sometimes the evolving battlefield is more of an unexpected plot twist that occurs in the middle of the encounter. Perhaps the evil tyrant reveals that they were a dragon all along, or reinforcements arrive for whichever side was outmatched. Whatever you choose, make sure it changes things up and makes the encounter feel more dynamic and different. For instance, raising up a portion of the battlefield that isn't particularly relevant when neither the PCs nor their foes are likely to care is less interesting than raising up the pedestal holding the jewel the PCs and their enemies are trying to recover.

Combining and Separating Encounters

Source GM Core pg. 79
Picture this: the PCs storm a castle. They choose to eschew stealth in favor of a direct approach. On the ramparts, a guard spots them and raises an alarm. The sound of horns and whistles blares throughout the keep as each defender ensures that everyone is ready for a fight. And then, they politely wait in whatever room they were already standing in for the PCs to come and attack them. It sounds pretty unrealistic, and it feels unrealistic at the table. Many players find it far more satisfying when their foes take reasonable actions and countermeasures against them, such as moving to defensible positions or banding together with allies. Taken to an extreme, combining encounters can quickly lead to fights that are unwinnable, so be careful. In the castle example, some guards may come out to attack the PCs, while others cluster around the central keep. Perhaps each individual patrol of guards around the castle is a trivial-threat encounter, but as they gather together, they form groups of gradually escalating threat. Such groups give the PCs a sense of how challenging their opposition is, so that if a fight against six guards is a challenge, they won't try to pick a fight with 30. When the PCs' foes amass into an overwhelming force, give the PCs fair warning and a chance to retreat and try again another day. Of course, if the PCs come back after the alarm has been raised, the guards are likely to change their rotations to better secure the keep.

The most common reason to separate an encounter into multiple pieces is to set up a combined encounter, like when an injured foe retreats to gather reinforcements. This provides the PCs with a choice: do they ignore the fleeing enemy and focus on the battle in front of them, or do they split their own forces, weighing the risk of being led into a dangerous encounter against the chance of stopping later foes from preparing for their approach? An encounter might also separate into pieces because of dramatic changes to the battlefield, such as a collapsing ceiling or a magical wall that prevents those on each side of the barrier from accessing the other without spending actions to bypass the obstruction.

Time Pressure

Source GM Core pg. 79
Time pressure adds an extra sense of urgency to any encounter and can be a great way to make an otherwise trivial- or low-threat encounter tactically engaging, satisfying, and memorable. After all, while low- and trivial-threat encounters have an incredibly low chance of defeating the PCs, the opposition can usually hold on long enough to make the PCs spend a few rounds to defeat them unless the PCs expend more resources than they normally would on such foes. Time pressure is often related to a secondary objective in the encounter, though it could be a countdown directly related to the encounter itself. For instance, if the ritual will grant a lich its apotheosis in 4 rounds, the heroes need to defeat the lich before then!

Secondary Objectives

Source GM Core pg. 79
One of the simplest and most exciting ways to create a dynamic encounter, even if the combat itself is not so difficult, is to add a secondary objective beyond simply defeating foes. Perhaps the villains are about to burn captives in a fire, and some of the PCs need to divert their efforts to avoid a pyrrhic victory. Encounters with a parallel objective that require PCs to take actions other than destroying foes can keep those foes around long enough to do interesting things without inflating their power level. It also gives PCs skilled in areas related to the side mission a chance to shine.

Sometimes a secondary objective might present a time limit, like if the PCs need to prevent evidence from being burned, either by fighting quickly or by actively protecting the documents. Another type of secondary objective relates to how the PCs engage in combat with the primary opposition. The PCs might need to use nonlethal attacks against guards who mistakenly believe the PCs are criminals, or they might need to prevent slippery scouts from retreating to alert others. Options like these highlight mobile characters like the monk. You could even create truly off-the-wall secondary objectives that require the PCs to lose the encounter in order to succeed. The PCs might need to put up a believable fight but retreat and let foes steal their caravan in order to follow the foes back to their lair. Secondary objectives are a great way to highlight different abilities in combat and make for a memorable encounter, but—like all of these tactics—they can become annoying if overused.

Opponent Synergy

Source GM Core pg. 80
Most encounters assume that the PCs' opponents work together to oppose the PCs, but when groups of foes have been collaborating and fighting together for a long time, they can develop additional strategies. Consider giving each member of these tightly knit teams a reaction triggered by their allies' abilities, or another benefit they gain based on their allies' actions. Just as a team of PCs learns how to best position the rogue to flank enemies and minimize the harm they take from the wizard's fireball spell, NPCs can learn to complement each other's strategies and avoid interfering with each other. On the opposite end of the spectrum, opponents with poor coordination make the fight much easier for the PCs. Poor coordination between mindless creatures is common, and PCs can use clever tactics to run circles around these foes. When intelligent creatures accidentally (or deliberately) harm each other or pursue conflicting strategies, particularly if they engage in banter with each other as they fight, it can make for an amusing break in the typical rhythm of combat.

When taken to its extreme, synergy can represent the actions of a hive mind or a single massive creature. These synergistic components can be creatures, hazards, or both. For example, instead of representing a kraken the size of a warship as a single foe, you could represent each of its tentacles as an individual opponent. Perhaps the kraken can sacrifice actions it would otherwise use to crush PCs in its maw to use its tentacles more freely. In this case, you could model a field of tentacles as a complex hazard that mainly reacts to the PCs moving within it, but allow the kraken's head to act with a few tentacles directly.


Source GM Core pg. 80
Sometimes, a bit of misdirection can add a lot of interest to an encounter, especially against offense-heavy groups. Rather than amping up the opposition to match the PCs' firepower and creating opponents whose own offenses are too powerful for the PCs' defenses, consider a little sleight of hand. For instance, a villain might have an illusory or disguised decoy target with just enough durability to take a few hits while the true villain is hiding nearby, ready to emerge and attack. Illusion spells can allow a foe to attack from a safer position, and possession grants the foe a disposable body unless the PCs brought along spirit blast or similar magic. Sometimes you can even hide the villain in plain sight: for instance, in an encounter with three goblins with similar-looking gear and an ogre, one of the goblins might be the biggest threat, but the PCs are likely to target the ogre first.

Care when setting up the battle map can also go a long way to misdirect your players—or at least avoid accidentally telegraphing what an encounter will be. For instance, if you always put out statue minis whenever there are statues in the room, the PCs might at first be overly suspicious of ordinary statues, but they will be more surprised later on when a statue turns out to be a construct than if you place minis only when the statue is actually a construct.

Recurring Villains

Source GM Core pg. 81
Not every villain dies the first time the PCs defeat them in combat. Some may escape, perhaps through teleportation, misdirection, or with other ploys. When a villain escapes and lives to fight the PCs again another day, it’s good to have that foe learn from their past failures. In their next encounter with the PCs, give them additional minions, spells, or other defenses designed to counteract the strategies the PCs used against them previously. Even if the villain doesn’t escape, they might have other tricks up their sleeves, such as rising again to oppose the PCs. They could well return later in the adventure—or they might come back immediately for a second battle, so long as there is a proper justification for doing so. For example, defeating an otherworldly villain’s outer shell might reveal its terrible true form, or a previously living necromancer might rise again as an undead monstrosity bent upon destroying the PCs.

Social Encounters

Source GM Core pg. 81
Details on how to run a social encounter, and the differences between a social and combat encounter, appear on page 31. The setup for a social encounter tends to be less detailed. For the NPCs involved, you'll just need statistics for their social skills, Perception, and Will. These use the non-combat level of the creature (page 31), based on the creature's social skills, not its combat level. You determine the challenge of a social encounter based on this non-combat level.

You also need to decide the objective or consequences of the social encounter—what the PCs can achieve and what happens if they fail—and the form of the challenge. It might be a public debate, a private audience with a powerful person, or some kind of contest. Just like with combat encounters, think about the environment, with a particular eye toward the other people around. Is there a crowd the PCs can sway? Are they in an imposing, luxurious throne room or at a city gate? Is the atmosphere oppressive? Hopeful?

You might find the PCs' goals end up being quite different from what you initially thought they would be. Fortunately, social encounters are adaptable. Thinking of their likely objective helps you construct the scene in your mind more easily but shouldn't limit you.

Treasure by Encounter

Source GM Core pg. 81
The standard rules count treasure over the course of a level, rather than dividing it up by encounter. If you need to select treasure for a single encounter, such as in a sandbox game, you can use the table below. It takes the treasure budget for each level and breaks that down per encounter based on the encounter threat, similar to how XP varies by threat. The final column shows extra treasure you should award if you build an entire level this way. Unlike the standard table, this doesn’t include items by item level, as the value doesn’t cleanly break down for most single encounters. It’s recommended you still give out those permanent items, but you’ll need to borrow from other encounters’ treasure to account for their value. Include encounters against creatures without treasure to account for this.

Table 5-3: Treasure by Encounter

LevelTotal Treasure per LevelLowModerateSevereExtremeExtra Treasure
1175 gp13 gp18 gp26 gp35 gp35 gp
2300 gp23 gp30 gp45 gp60 gp60 gp
3500 gp38 gp50 gp75 gp100 gp100 gp
4850 gp65 gp85 gp130 gp170 gp170 gp
51,350 gp100 gp135 gp200 gp270 gp270 gp
62,000 gp150 gp200 gp300 gp400 gp400 gp
72,900 gp220 gp290 gp440 gp580 gp580 gp
84,000 gp300 gp400 gp600 gp800 gp800 gp
95,700 gp430 gp570 gp860 gp1,140 gp1,140 gp
108,000 gp600 gp800 gp1,200 gp1,600 gp1,600 gp
1111,500 gp865 gp1,150 gp1,725 gp2,300 gp2,300 gp
1216,500 gp1,250 gp1,650 gp2,475 gp3,300 gp3,300 gp
1325,000 gp1,875 gp2,500 gp3,750 gp5,000 gp5,000 gp
1436,500 gp2,750 gp3,650 gp5,500 gp7,300 gp7,300 gp
1554,500 gp4,100 gp5,450 gp8,200 gp10,900 gp10,900 gp
1682,500 gp6,200 gp8,250 gp12,400 gp16,500 gp16,500 gp
17128,000 gp9,600 gp12,800 gp19,200 gp25,600 gp25,600 gp
18208,000 gp15,600 gp20,800 gp31,200 gp41,600 gp41,600 gp
19355,000 gp26,600 gp35,500 gp53,250 gp71,000 gp71,000 gp
20490,000 gp36,800 gp49,000 gp73,500 gp98,000 gp98,000 gp