Building Hazards

The first thing you'll need is a concept for your hazard. What level is your hazard? Will it be simple or complex? Is it a trap, a haunt, an environmental hazard, or something else? If it's a trap, is it mechanical, magical, tech, or all of the above? This is a good time to consider the hazard's description and how to disable it.

Statistics determine how your hazard interacts with the game world, representing how dangerous it is and how hard it is to render harmless or circumvent. The statistics for your hazard can have extreme, high, or low values. You'll want to choose the value that's most appropriate for the concept of your hazard while ensuring that it's well balanced to ensure a fun encounter.

Extreme: The hazard is world-class in this statistic and can challenge almost any character. Almost all hazards have one extreme statistic because hazards normally activate only if they've gone unnoticed or if someone critically failed to disable them. Does it have an extreme Stealth DC that makes it incredibly hard to find, an extreme Disable DC that makes it perilous to disable, or an extreme save DC that makes it deadly in the event it triggers? These are the most common choices, as each affects a different phase of encountering the hazard.

High: Extremely capable but not world-class, the hazard presents a challenge for most characters. This is a capable level and can generally serve as a baseline value.

Low: If a hazard has a weakness, like a poor Reflex save for a bulky mechanical trap or an easy DC to disable for a hard-to-find trap, it usually has a low value. If you need something even lower, use a terrible value from Building Creatures, or just an incredibly low value.

When determining a hazard's combat statistics, first decide how the hazard can be located and how hard it is to disable. A hazard where the main challenge is how difficult it is to find, like memory crystals, might have a very different effect for its level than a hazard out in plain sight, daring a PC to try to disable it, like the laser turret or the monument to the Devourer.

When deciding how your hazard is disabled, come up with a narrative description of how it would happen, which will inform which methods and skills disable the hazard. You'll need to decide the proficiency rank necessary to find the hazard as well as disable it with each method. Remember, a hazard without a listed rank next to its Stealth DC is obvious enough that creatures can find it without Searching, and magical hazards without a listed rank aren't normally protected against detect magic. Most hazards built by intelligent creatures are concealed and have at least a trained rank. The Minimum Proficiency table indicates the high and moderate proficiency requirements by level; you can use lower proficiency ranks than the ones listed, and if you use the high rank, consider a secondary, perhaps less-efficient method to disable the hazard using a lower rank. For instance, the exploding egg sac environmental hazard can be disabled with expert Survival, or by a higher DC with trained Nature.

If you need a Stealth modifier for a complex hazard, just subtract 10 from the listed DC.

If there's a physical component that a character could break, you'll need to determine the hazard's AC, Fortitude save, and Reflex save, using the extreme, high, and low values (preceded by E, H, or L on the Hazard Defenses table) as well as its Hardness, HP, and Broken Threshold (BT). When building a purely magical or formless hazard, you can skip this section.

Some hazards, even high-level ones, don't make sense with a high Hardness value. In those cases, you can skip the Hardness and use the HP values from the Hit Points table. Especially for complex hazards, you might want to divide the durability over multiple sections, located in different positions, to encourage teamwork and mobility.

Almost all hazards need an attack bonus or a save DC, and hazards that deal damage need to list a damage value. Simple hazards deal about twice as much damage as complex hazards and have a very high attack bonus (abbreviated as S. Atk in the Hazard Offense table on page 115). Complex hazards usually have more moderate attack bonuses (abbreviated as C. Atk in the table). You can adjust them further using the Strike Attack Bonus table on page 124 if your hazard needs it. Simple hazard DCs aren't as high for their level as their attack bonuses are since effects with DCs usually have some effect even on a successful saving throw; use the EDC and HDC columns for extreme and hard DCs in the table.

The damage columns on the table give a damage expression you can use, followed by the average damage in parentheses. If you want to make your own damage expression, remember that average damage is 2.5 for a d4, 3.5 for a d6, 4.5 for a d8, 5.5 for a d10, and 6.5 for a d12.

When designing a simple hazard, make sure to select an appropriate trigger and effect. Often, a simple hazard that merely damages its target is little more than a speed bump that slows down the game without much added value, so think about the purpose of your hazard carefully, both in the story and in the game world, especially when it's a hazard that a creature intentionally built or placed in that location. A great simple hazard does something interesting, has a longer-lasting consequence, or integrates with the nearby inhabitants or encounters in some way (as discussed under Dynamic Encounters).

Unlike a simple hazard, a complex hazard can play the part of a creature in a battle or can be an encounter all its own. Many of the concerns with damaging effects when designing a simple hazard don't apply when designing a complex hazard. A complex hazard can deal its damage over and over again and isn't intended to be quick to overcome.

A good complex hazard often requires disabling multiple components or otherwise interacting with the encounter in some way. For instance, while the haywire autopilot can be remotely reprogrammed with a challenging Computers check, characters who want to use Piloting or Thievery to override the autopilot will first need to board the vehicle using Acrobatics or Athletics.