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Archives of Nethys

Archives of Nethys

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GM Core / Chapter 2: Building Games

Building Hazards

Source GM Core pg. 109 2.0
Building hazards designed for your game allows you to customize them to match your story, location, and needs, as well as to surprise the other players at every turn. There’s no wrong way to create a hazard, but this guide presents the information in the order you might see it in a hazard stat block.

Concept

Source GM Core pg. 109 2.0
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, or both? This is a good time to brainstorm the hazard’s name and description, as this will help you decide how the hazard can be disabled.

Hazard Types

Source GM Core pg. 109 2.0
The three main types of hazards are traps, environmental hazards, and haunts.

Traps are usually built or placed. They can also form accidentally, such as if a magic portal, through millennia of disuse, malfunctions as its magic warps. Mechanical traps always have some physical component, whereas purely magical traps typically don't. Magical traps can usually be counteracted by dispel magic, and those without a listed proficiency rank for Stealth can be found using detect magic. Thievery is the most common skill used to disable traps. Environmental hazards are either living things, like dangerous spores and molds, or simply features of the terrain or environment, like avalanches or rockslides. While they are always physical, some environmental hazards can't reasonably be attacked or damaged, such as a cloud of poisonous gas or a patch of quicksand. Survival is the most common skill used to disable environmental hazards.

Haunts are spiritual hazards, usually formed when the spiritual essence of a location is imprinted with the instincts and emotions from a living being's demise. Because haunts lack matter, they rarely involve a physical component, and when they do, that component is generally incorporeal or might even be damaged only by vitality energy. The skills and options used to disable haunts vary, though using Religion for an exorcism is common. However, even with a successful check to disable a haunt, it can reoccur until its unfinished business is resolved. Typically, successfully disabling or enduring a haunt provides clues to determine what it would take to lay it to rest permanently.

Understanding and Choosing Statistics

Source GM Core pg. 109 2.0
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 will want to choose the value that is most appropriate for the concept of your hazard, while ensuring that it is 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 have 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 (pages 112–125), or just an incredibly low value like the armageddon orb's Stealth (page 100).

Stealth and Disable

Source GM Core pg. 110 2.0
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 the hidden pit, 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 armageddon orb.

Table 2–13: Stealth and Disable DCs

LevelExtremeHighLow
–1181512 to 11
0191613 to 12
1201714 to 13
2211815 to 14
3232017 to 15
4252218 to 17
5262320 to 18
6282521 to 19
7302723 to 21
8312824 to 22
9333026 to 23
10353227 to 25
11363329 to 26
12383530 to 27
13403732 to 29
14413833 to 30
15434035 to 31
16454236 to 33
17464338 to 34
18484539 to 35
19504741 to 37
20514842 to 38
21535044 to 39
22555245 to 41
23565346 to 42
24585548 to 43

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 are not 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 lessefficient method to disable the hazard using a lower rank. For instance, the bloodthirsty urge haunt (page 100) can be disabled with master Religion, or by a higher DC with expert Diplomacy.

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

Table 2–14: Minimum Proficiency

LevelsHighModerate
0 or lowerUntrainedUntrained
1–4Trained (expert for Perception)Trained
5–8ExpertTrained
9–18MasterExpert
19 or higherLegendaryMaster

Defenses

Source GM Core pg. 110 2.0
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 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 table 2–7: Hit Points on page 63. Especially for complex hazards, you might want to divide the durability over multiple sections, located in different positions, to encourage teamwork and mobility.

Table 2–15: Defenses

LevelEACHACLACE SaveH SaveL SaveHardnessHP*
–1181512+9+8+22–411–13
0191613+10+9+33–515–17
1191613+11+10+45–723–25
2211815+12+11+57–930–34
3221916+14+12+610–1242–46
4242118+15+14+811–1346–50
5252219+17+15+912–1450–54
6272421+18+17+1113–1554–58
7282522+20+18+1214–1658–62
8302724+21+19+1315–1762–66
9312825+23+21+1516–1866–70
10333027+24+22+1617–1970–74
11343128+26+24+1819–2178–82
12363330+27+25+1920–2282–86
13373431+29+26+2021–2386–90
14393633+30+28+2222–2490–94
15403734+32+29+2323–2594–98
16423936+33+30+2525–27101–107
17434037+35+32+2627–29109–115
18454239+36+33+2729–31117–123
19464340+38+35+2931–33125–131
20484542+39+36+3033–35133–139
21494643+41+38+3236–38144–152
22514845+43+39+3339–41156–164
23524946+44+40+3444–46168–176
24545148+46+42+3646–50180–188
* The Broken Threshold is usually half the hazard’s HP.

Offense

Source GM Core pg. 111 2.0
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 table). Complex hazards usually have more moderate attack bonuses (abbreviated as C. Atk in the table). You can adjust them further using the Attack Bonus table on page 120 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.

Table 2–16: Offense

LevelS. AtkC. AtkSimple DmgComplex DmgEDCHDC
–1+10+82d4+1 (6)1d4+1 (3)1916
0+11+82d6+3 (10)1d6+2 (5)1916
1+13+92d6+5 (12)1d6+3 (6)2017
2+14+112d10+7 (18)1d10+4 (9)2218
3+16+122d10+13 (24)1d10+6 (12)2320
4+17+144d8+10 (28)2d8+5 (14)2521
5+19+154d8+14 (32)2d8+7 (16)2622
6+20+174d8+18 (36)2d8+9 (18)2724
7+22+184d10+18 (40)2d10+9 (20)2925
8+23+204d10+22 (44)2d10+11 (22)3026
9+25+214d10+26 (48)2d10+13 (24)3228
10+26+234d12+26 (52)2d12+13 (26)3329
11+28+244d12+30 (56)2d12+15 (28)3430
12+29+266d10+27 (60)3d10+14 (30)3632
13+31+276d10+31 (64)3d10+16 (32)3733
14+32+296d10+35 (68)3d10+18 (34)3934
15+34+306d12+33 (72)3d12+17 (36)4036
16+35+326d12+35 (74)3d12+18 (37)4137
17+37+336d12+37 (76)3d12+19 (38)4338
18+38+356d12+41 (80)3d12+20 (40)4440
19+40+368d10+40 (84)4d10+20 (42)4641
20+41+388d10+44 (88)4d10+22 (44)4742
21+43+398d10+48 (92)4d10+24 (46)4844
22+44+418d10+52 (96)4d10+26 (48)5045
23+46+428d12+48 (100)4d12+24 (50)5146
24+47+448d12+52 (104)4d12+26 (52)5248

Designing Simple Hazards

Source GM Core pg. 111 2.0
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 even the encounters in some way (you can find more information on integrating hazards with encounters on page 78).

Designing Complex Hazards

Source GM Core pg. 111 2.0
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 apply its damage over and over again, eventually killing its hapless victim, and isn't intended to be a quick-to-overcome obstacle.

A good complex hazard often requires disabling multiple components or otherwise interacting with the encounter in some way. For instance, while the poisoned dart gallery (page 107) requires only one Thievery check to disable, the control panel is on the far end of the gallery, so a PC would need to make their way across first.

Building Routines

Source GM Core pg. 111 2.0
A complex hazard has a routine each round, whether it stems from preprogrammed instructions built into a trap, instincts and residual emotions swirling around a complex haunt, or a force of nature like sinking in quicksand. Make sure to build a routine that makes sense for the hazard; an environmental lava chute that ejects lava into the area each round shouldn't be able to seek out and precisely target only the PCs, but it might spatter random areas within range or everything within range, depending on how you describe the hazard. However, a complex haunt might be able to recognize life force and target living creatures.

If you create a hazard that can't consistently attack the PCs (like the blade pillar, which moves in a random direction), you can make it deadlier than normal in other ways.

The hazard should have as many actions as you feel it needs to perform its routine. If you split the routine out into several actions, you can also remove some of the hazard's actions once partial progress is made in disabling or destroying it; this can give the PCs a feeling of progress, and it can encourage them to handle the hazard if it appears in an encounter alongside creatures.