Traps
Traps are a common dungeon danger — from gouts of white-hot flame to hails of poisoned darts. All traps share the same stat block anatomy regardless of type, making them easy to read, design, and adjudicate at the table.
Mechanical Traps
Nonmagical — springs, pressure plates, blades, pits. Any character can attempt to find them with Perception and disable them with Disable Device.
- Base Perception and Disable Device DC: 20
- Can be built with Craft (traps)
- Detecting the mechanism reveals what the trap does (Perception DC +5)
Magic Traps
Spell-based — always allow a saving throw. Only characters with the trapfinding class feature can disarm them.
- Perception DC: 25 + spell level
- Disable Device DC: 25 + spell level (trapfinding required)
- Save DC: 10 + spell level × 1.5
- Building: requires Craft Wondrous Item feat
Trap Stat Block Anatomy
Every trap stat block lists these elements in order: Type · CR · Perception DC · Disable Device DC · Trigger · Reset · Effect. Optional elements appear as needed.
Wall Scythe Trap
CR 4
Type mechanical; Perception DC 20; Disable Device DC 20
Trigger location; Reset automatic
Effect Atk +20 melee (2d4+6/×4)
Type
Mechanical or Magic. Determines which DCs apply,
who can disarm it, and how it is built.
Perception & Disable Device DCs
The builder sets both DCs for mechanical traps (base 20); adjusting them up or
down changes the trap's CR. For magic traps both DCs equal 25 + highest spell level used.
Trigger
Location
Springs when a creature stands in a specific square. Flying creatures bypass it.
Proximity
Springs when a creature approaches within a set distance. Works on flying creatures. Mechanical proximity triggers are sensitive to air movement — usable only in very still areas.
Sound
Magic only. +15 Perception. Defeated by Stealth, silence, and similar effects. Requires clairaudience during construction.
Visual
Magic only. Functions like an eye.
Range and bonus depend on construction spell:
arcane eye (line of sight, +20),
clairvoyance (preselected location, +15),
true seeing (120 ft., +30).
Invisibility and illusions that fool the spell also fool the trigger.
Touch
Springs when the trigger mechanism is touched. May be physically attached to the damaging part or separate.
Timed
Springs periodically after a set duration has passed.
Spell
All spell traps use this trigger. See the spell description for conditions.
Reset
None — one-shot; spell traps are always no reset.
Repair — Craft (traps) check to rebuild; costs 1/5 of original market price.
Manual — someone moves the parts back into position. Most common for mechanical traps.
Automatic — resets itself, either immediately or after a timed interval. Adds +1 to CR.
Duration
Most traps are instantaneous — they trigger and stop. Some have a duration in rounds,
affecting all creatures at the top of initiative order (or when activated) each round
until the duration expires.
Bypass (optional)
Lets the builder move past the trap safely. Mechanical traps only (spell traps
have built-in caster allowances).
- Lock — DC 30 Disable Device to open
- Hidden Switch — DC 25 Perception to locate
- Hidden Lock — DC 25 Perception + DC 30 Disable Device
Effect Types
Pit — Reflex save to avoid (DC set by builder); 1d6 per 10 ft. of depth. May include spikes, liquid, or a secondary trap at the bottom.
Ranged Attack — Normal attack roll (darts, arrows, spears). Builder sets attack bonus.
Melee Attack — Blades, falling blocks, etc. Builder sets attack bonus and damage.
Spell Trap — Produces a spell's effect. Save DC = 10 + spell level + caster's ability modifier.
Magic Device — Like a wand or rod going off. Save DC = (10 + spell level) × 1.5.
Miscellaneous Features
Alchemical Item — tanglefoot bags, alchemist's fire, etc. CR modifier = spell level of mimicked effect.
Gas — inhaled poison delivery; always pairs with Never Miss + Onset Delay.
Liquid — drowning danger; always pairs with Never Miss + Onset Delay. CR +5.
Multiple Targets — can affect more than one creature. CR +1 (non-damage).
Never Miss — no attack roll or saving throw; always has Onset Delay. CR +2.
Onset Delay — time between springing and damage. Required for Never Miss traps.
Pit Spikes — treat as daggers with +10 attack; +1 damage per 10 ft. depth (max +5); 1d4 spikes per target. Damage is in addition to fall damage.
Poison — injury, contact, or inhaled only (no ingested). CR modifier varies by poison type.
Touch Attack — only needs a successful touch attack to hit. CR +1.
Finding & Disabling Traps
| Trap Type | Perception DC | Disable Device DC | Who Can Disarm | Detect +5 Reveals |
|---|---|---|---|---|
| Mechanical | Set by builder (base 20) | Set by builder (base 20) | Any character | What the trap does |
| Magic | 25 + highest spell level | 25 + highest spell level | Trapfinding only | — |
Creatures that succeed on Perception detect the triggering mechanism (pressure plate, odd gears, etc.) before the trap activates. Beating the DC by 5 or more gives a general idea of what the trap does. Disable Device takes 2d4 rounds; failing by 5 or more springs the trap.
Sample Traps
26 sample stat blocks from the Core Rulebook, ordered by CR.
| CR | Name | Type | Perc DC | DD DC | Trigger | Reset | Effect |
|---|---|---|---|---|---|---|---|
| 1 | Arrow Trap | Mech | 20 | 20 | Touch | None | Atk +15 ranged (1d8+1/×3) |
| 1 | Pit Trap | Mech | 20 | 20 | Location | Manual | 20-ft. pit (2d6 fall); DC 20 Reflex avoids; 10-ft. square |
| 1 | Poisoned Dart Trap | Mech | 20 | 20 | Touch | None | Atk +10 ranged (1d3 + greenblood oil) |
| 1 | Swinging Axe Trap | Mech | 20 | 20 | Location | Manual | Atk +10 melee (1d8+1/×3); 10-ft. line |
| 2 | Burning Hands Trap | Magic | 26 | 26 | Proximity (alarm) | None | burning hands (2d4 fire; DC 11 Reflex half); 15-ft. cone |
| 2 | Javelin Trap | Mech | 20 | 20 | Location | None | Atk +15 ranged (1d6+6) |
| 2 | Spiked Pit Trap | Mech | 20 | 20 | Location | Manual | 10-ft. pit (1d6 fall); spikes (Atk +10, 1d4 spikes for 1d4+2 ea.); DC 20 Reflex avoids; 10-ft. square |
| 3 | Acid Arrow Trap | Magic | 27 | 27 | Proximity (alarm) | None | acid arrow (Atk +2 ranged touch; 2d4 acid for 4 rounds) |
| 3 | Camouflaged Pit Trap | Mech | 25 | 20 | Location | Manual | 30-ft. pit (3d6 fall); DC 20 Reflex avoids; 10-ft. square |
| 4 | Electricity Arc Trap | Mech | 25 | 20 | Touch | None | 4d6 electricity; DC 20 Reflex half; 30-ft. line |
| 4 | Wall Scythe Trap | Mech | 20 | 20 | Location | Automatic | Atk +20 melee (2d4+6/×4) |
| 5 | Falling Block Trap | Mech | 20 | 20 | Location | Manual | Atk +15 melee (6d6); 10-ft. square |
| 5 | Fireball Trap | Magic | 28 | 28 | Proximity (alarm) | None | fireball (6d6 fire; DC 14 Reflex half); 20-ft.-radius burst |
| 6 | Flame Strike Trap | Magic | 30 | 30 | Proximity (alarm) | None | flame strike (8d6 fire; DC 17 Reflex half); 10-ft.-radius cylinder |
| 6 | Wyvern Arrow Trap | Mech | 20 | 20 | Location | None | Atk +15 ranged (1d6 + wyvern poison/×3) |
| 7 | Frost Fangs Trap | Mech | 25 | 20 | Location | None | Jets of freezing water (3d6 cold; DC 20 Reflex half); 40-ft.-square chamber; 3 rounds |
| 7 | Summon Monster VI Trap | Magic | 31 | 31 | Proximity (alarm) | None | summon monster VI (1d3 Large elementals or 1 Huge elemental) |
| 8 | Camouflaged Spiked Pit Trap | Mech | 25 | 20 | Location | Manual | 50-ft. pit (5d6 fall); spikes (Atk +15, 1d4 spikes for 1d6+5 ea.); DC 20 Reflex avoids; 10-ft. square |
| 8 | Insanity Mist Trap | Mech | 25 | 20 | Location | Repair | Poison gas (insanity mist); never miss; onset delay 1 round; 10-ft.×10-ft. room |
| 9 | Hail of Arrows Trap | Mech | 25 | 25 | Visual (arcane eye) | Repair | Atk +20 ranged (6d6); 20-ft. line |
| 9 | Shocking Floor Trap | Magic | 26 | 26 | Proximity (alarm) | None | shocking grasp (Atk +9 melee touch; 4d6 electricity); 40-ft.-square room; 1d6 rounds |
| 10 | Chamber of Blades Trap | Mech | 25 | 20 | Location | Repair | Atk +20 melee (3d8+3); 20-ft.-square chamber; 1d4 rounds |
| 10 | Energy Drain Trap | Magic | 34 | 34 | Visual (true seeing) | None | energy drain (Atk +10 ranged touch; 2d4 neg. levels; DC 23 Fort negates after 24 hrs.) |
| 11 | Cone of Cold Trap | Magic | 30 | 30 | Proximity (alarm) | None | cone of cold (15d6 cold; DC 17 Reflex half); 60-ft. cone |
| 12 | Poisoned Pit Trap | Mech | 25 | 20 | Location | Manual | 50-ft. pit (5d6 fall); spikes + shadow essence poison; DC 25 Reflex avoids; 10-ft. square |
| 13 | Maximized Fireball Trap | Magic | 31 | 31 | Proximity (alarm) | None | fireball maximized (60 fire damage; DC 14 Reflex half); 20-ft.-radius burst |
| 14 | Harm Trap | Magic | 31 | 31 | Touch | None | harm (Atk +6 melee touch; 130 damage; DC 19 Will half; min 1 HP) |
| 15 | Crushing Stone Trap | Mech | 30 | 20 | Location | Manual | Atk +15 melee (16d6); 10-ft. square |
| 16 | Empowered Disintegrate Trap | Magic | 33 | 33 | Sight (true seeing) | None | disintegrate empowered (Atk +9 ranged touch; 30d6+50%; DC 19 Fort → 5d6+50%) |
| 17 | Lightning Bolt Gallery Trap | Magic | 29 | 29 | Proximity (alarm) | None | lightning bolt heightened (8d6 electricity; DC 16 Reflex half); 60-ft.-square chamber; 1d6 rounds |
| 18 | Deadly Spear Trap | Mech | 30 | 30 | Sight (true seeing) | Manual | Atk +20 ranged (1d8+6 + black lotus extract) |
| 19 | Meteor Swarm Trap | Magic | 34 | 34 | Sight (true seeing) | None | meteor swarm (4 meteors; Atk +9 ranged touch; 2d6+6d6 fire per hit; 18d6 fire splash; DC 23 Reflex half); 4 targets |
| 20 | Destruction Trap | Magic | 34 | 34 | Proximity (alarm) | None | destruction heightened (190 damage; DC 23 Fort → 10d6) |
Designing a Trap
Select the elements you want, sum the CR modifiers, and arrive at the final CR. The CR determines the Craft (traps) DC and the market price.
CR Modifiers — Mechanical Traps
| Feature | CR Modifier |
|---|---|
| Perception DC | |
| 15 or lower | −1 |
| 16–20 | — |
| 21–25 | +1 |
| 26–29 | +2 |
| 30+ | +3 |
| Disable Device DC | |
| 15 or lower | −1 |
| 16–20 | — |
| 21–25 | +1 |
| 26–29 | +2 |
| 30+ | +3 |
| Reflex Save DC (pits / save-dependent) | |
| 15 or lower | −1 |
| 16–20 | — |
| 21–25 | +1 |
| 26–29 | +2 |
| 30+ | +3 |
| Attack Bonus (melee or ranged) | |
| +0 or lower | −2 |
| +1 to +5 | −1 |
| +6 to +10 | — |
| +11 to +15 | +1 |
| +16 to +20 | +2 |
| Touch attack | +1 |
| Damage / Effect | |
| Average damage | +1 per 10 pts |
| Miscellaneous | |
| Alchemical device | Level of spell mimicked |
| Automatic reset | +1 |
| Liquid | +5 |
| Multiple targets (non-damage) | +1 |
| Never miss | +2 |
| Proximity or visual trigger | +1 |
| Poison | |
| Greenblood oil / Bloodroot / Blue whinnis / Small centipede / Black adder venom | +1 |
| Medium spider venom | +2 |
| Giant wasp / Large scorpion / Malyass root / Sassone leaf / Shadow essence / Ungol dust | +3 |
| Insanity mist / Nitharit / Purple worm | +4 |
| Deathblade / Terinav root / Wyvern | +5 |
| Burnt othur fumes / Dragon bile | +6 |
| Black lotus extract | +8 |
CR Modifiers — Magic Traps
| Feature | CR Modifier |
|---|---|
| Highest-level spell effect | + Spell level |
| Damaging spell effect | +1 per 10 pts avg dmg |
| Use whichever modifier is larger — they do not stack. | |
Craft (Traps) DCs — Mechanical
| Trap CR | Base DC |
|---|---|
| 1–5 | 20 |
| 6–10 | 25 |
| 11–15 | 30 |
| 16+ | 35 |
| +5 DC for proximity trigger or automatic reset. | |
Cost — Mechanical Traps
Base: 1,000 gp × CR. No reset: halve cost. Automatic reset: add 50%.
Add the cost of any alchemical items or poison separately.
For auto-reset traps, multiply poison/alchemical cost ×20 for supply.
Simple traps (pits) may cost as little as 250 gp × CR.
Cost — Magic Device Traps
| Feature | Cost Modifier |
|---|---|
| Alarm spell in trigger | Free |
| One-Shot Trap | |
| Each spell | +50 gp × CL × spell level |
| Material components | + Material cost |
| Automatic Reset Trap | |
| Each spell | +500 gp × CL × spell level |
| Material components | + Material cost ×100 |
| Building time: 1 day per 500 gp of cost. Requires Craft Wondrous Item feat. | |