Rules Index | GM Screen | Player's Guide


Chapter 2: Building Games / Encounter Design

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
Low6015
Moderate8020
Severe12030
Extreme16040

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.