Introduction
Detection rules decide who can target whom, who has to guess, who has to Seek, and who is about to be stabbed by something they technically heard but did not locate. PF2e is picky here because stealth, invisibility, darkness, scent, cover, smoke, and monster senses all change action choices.
The shortcut is simple: name the sense, classify the sense, then name the awareness state. Once you do that, most detection arguments shrink from "Can I see it?" to "Is it observed, hidden, undetected, or unnoticed?"
The Three-Step Procedure
| Step | Question | Table Result |
|---|---|---|
| Name the sense ● | Are you using sight, hearing, scent, tremorsense, lifesense, wavesense, magic, or another sense? | The answer decides which obstacles matter. Darkness hurts sight, not scent. Silence hurts hearing, not tremorsense. |
| Classify the sense ● | Is that sense precise, imprecise, or vague? | Precise can observe. Imprecise can usually locate enough to make hidden. Vague can warn without giving a clean space. |
| Name the state ● | Is the target observed, concealed, hidden, undetected, unnoticed, or invisible? | The state tells you whether targeting is normal, uses a flat check, requires guessing, or needs more information first. |
Hot take: most stealth confusion is not caused by the rules being impossible. It is caused by the table skipping step one and then arguing about step three.
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Sense Types
| Sense Type | Practical Meaning | Examples And Links |
|---|---|---|
| Precise ● | Can perceive enough detail to make a creature observed and targeted normally unless something interferes. | Normal sight, some special senses, bright light, clear line of sight. Use with conditions. |
| Imprecise ● | Can usually tell a creature's location, but the creature is still hidden rather than observed. | Hearing, scent, spiritsense, wavesense, many monster senses. Use with Seek and creature traits. |
| Vague ● | Can reveal that something is present but not where it is in a usable way. | Ordinary smell for most characters, faint tremors, distant sound, atmospheric clues. Use with GM screen reference. |
Precise senses are the clean targeting senses. Imprecise senses are strong information tools but usually leave targeting uncertainty. Vague senses are clues, not coordinates.
Awareness States
| State | What The Observer Knows | What Changes |
|---|---|---|
| Observed ● | The observer can perceive the creature clearly. | Normal targeting unless another rule, cover, or concealment applies. |
| Concealed ● | The observer generally knows the space, but the target is hard to see clearly. | Targeting can require a flat check before the attack or effect resolves. |
| Hidden ● | The observer knows the creature's space but not its exact position. | Targeting is uncertain, the observer is off-guard to the hidden creature, and area effects remain useful. |
| Undetected ● | The observer does not know the creature's exact space. | The observer may need to Seek, guess a square, use an area effect, or change plans. |
| Unnoticed ● | The observer does not know the creature is present at all. | This is strongest before initiative, ambush, or a reveal. Do not narrate it away by accident. |
| Invisible ● | The creature cannot be seen by sight-based observers. | Sight alone does not observe it, but Seek, other senses, area effects, and clues can still matter. |
Observed is not the default once someone uses Stealth successfully. Hidden is not the same as undetected. Invisible is not the same as immune to being found. Unnoticed is not "the GM forgot to mention a monster"; it is a specific information state.
Common Detection Actions
| Action Or Activity | Best Use | Watch For |
|---|---|---|
| Seek ● | Scan an area for creatures, objects, hazards, secret doors, illusions, and other hidden information. | It is usually a secret Perception check, and the searched area is limited by the GM. |
| Point Out ● | Share a creature's location with allies when you know where it is and they do not. | Knowing a location yourself does not automatically update the whole party. |
| Hide ● | Become hidden when cover, concealment, or another factor supports hiding. | If a creature successfully Seeks you into observed, you must Hide again before Sneaking back toward undetected. |
| Sneak ● | Move while trying to remain hard to locate. | The payoff is changing location, not squatting forever in the obvious barrel square. |
| Search ● | Explore carefully for secret doors, traps, hidden objects, and suspicious details. | It trades speed for safety. Fast parties miss things. That is not unfair; that is the price of jogging through a dungeon. |
| Avoid Notice ● | Approach without being detected before encounter mode starts. | It can shape initiative and enemy awareness. Use with stealth in combat. |
| Scout ● | Improve the party's readiness by looking ahead. | It is not the same as searching every shelf, rune, and murder statue. |
Light, Darkness, Smoke, And Weather
| Scene Element | Detection Impact | Best Follow-Up |
|---|---|---|
| Bright light ● | Normal sight works cleanly for most creatures. | Use cover, distraction, invisibility, or actual Stealth support if you want to hide. |
| Dim light ● | Can create concealment for creatures without low-light vision. | Low-light vision matters here; link this to ancestry choices. |
| Darkness ● | Creatures without the right vision can lose clean sight entirely. | Darkvision, light, magical counters, scent, sound, and area effects become important. |
| Magical darkness ● | Can defeat ordinary darkvision depending on the effect. | Do not assume every darkvision creature wins automatically. |
| Smoke and fog ● | Often create concealment and flat-check pressure. | Alchemical items, consumables, and wind matter. |
| Rain and storms ● | Can obscure sight, sound, and tracks when the GM makes weather relevant. | Tengu and other sensory options can turn this from problem to advantage. |
| Water ● | Distortion can create concealment between underwater and above-water creatures. | Use environment, swim speeds, wavesense, and aquatic traits. |
GM Core encourages concrete environmental rulings. If smoke is thick enough to matter, say what it does. If darkness matters, say which creatures can see through it. If rain only adds flavor, do not pretend it secretly invalidates every ranged attack after the roll.
Player Core 2 Detection Hooks
| Option | Detection Angle |
|---|---|
| Catfolk ● | Hunting Catfolk can gain scent, Sharp-Eared Catfolk improve Seek by sound, and catfolk feats can turn finding a creature into pressure. |
| Hobgoblin ● | Smokeworker and Warrenbred options reduce smoke or underground concealment problems. |
| Kholo ● | Darkvision and scent options make tracking and nighttime fights cleaner. |
| Ratfolk ● | Deep Rat darkvision and Longsnout Rat scent push the ancestry toward scouting and pursuit. |
| Tengu ● | Stormtossed Tengu can ignore specific weather-based concealment, which is excellent in bad-weather campaigns. |
| Tripkee ● | Low-light and darkvision options support canopy, night, and ambush movement. |
| Dragonblood and dhampir ● | Versatile heritages can upgrade low-light vision or darkvision and change how darkness-heavy scenes feel. |
| Alchemist ● | Smoke, darkvision elixirs, sight enhancers, and anti-concealment tools make alchemy one of the best detection support kits. |
Class Lessons
| Class | Detection Lesson |
|---|---|
| Rogue ● | Stealth and off-guard pressure reward exact awareness-state play. |
| Ranger ● | Seek, Track, Hunt Prey, scouting, and ambush starts make information a combat stat. |
| Investigator ● | Strong Perception, clue work, and anti-concealment features turn uncertainty into advantage. |
| Monk ● | Speed and senses let the Monk reposition after detection changes. |
| Witch ● | Familiar senses and hex support can Point Out threats and cover unusual detection angles. Use companions and familiars for the creature procedure. |
| Wizard ● | Arcane detection, illusion counterplay, darkness, invisibility, and arcane spells make the Wizard a rules referee with a spellbook. |
| Druid ● | Primal scouting, animal senses, terrain, and weather interaction fit wilderness detection perfectly. See primal spells. |
| Gunslinger ● | Cover, smoke, range, noise, and reload timing make detection important but campaign-dependent. See firearms. |
Monster Core Senses
Monster senses are not decorative. A wolf with scent, an undead with darkvision, an incorporeal creature with lifesense, an aquatic creature with wavesense, and a devil with greater darkvision all challenge different assumptions.
| Monster Feature | Why It Matters | GM Reminder |
|---|---|---|
| Darkvision ● | Darkness stops being a hiding tool against many monsters. | Magical darkness may still matter, depending on the effect and sense. |
| Greater darkvision ● | Some creatures can see through stronger darkness effects. | Use this sparingly and clearly; it can erase a party's shadow plan. |
| Scent ● | Can locate creatures that sight misses, especially in close range. | Wind direction and strong odors can change effective range. |
| Lifesense and spiritsense ● | Living creatures, undead, spirits, and haunts can become detectable in ways sight does not cover. | It may locate without making the target observed. State the awareness state. |
| Tremorsense and wavesense ● | Ground and water movement can betray hidden creatures. | Flying, swimming, burrowing, and terrain can change whether the sense applies. |
| Light blindness or light sensitivity ● | Some darkness-adapted monsters hate bright light. | Give players clues so counterplay feels earned. |
Use creature traits, stat blocks, monster encounter use, and Monster Core 2 high-level threats when building scenes around unusual senses.
Illusions, Invisibility, And Magical Detection
Illusions often invite Seek, Interact, or disbelief checks. Invisibility can make a creature undetected to sight-based observers, but it does not erase sound, tracks, disturbed dust, scent, area effects, or special senses. Magical detection can find auras, creatures, or other clues depending on the spell.
The important GM habit is to separate "you cannot see it" from "you cannot know anything about it." A character might hear armor scrape, smell blood, see water ripple, notice footprints, or detect magic. Those clues may move a creature from unnoticed to undetected, from undetected to hidden, or from hidden to observed if the correct sense and action support it.
Use utility spells, cantrips, arcane spells, occult spells, and focus spells.
Common Mistakes
| Mistake | Fix |
|---|---|
| Treating hidden and undetected as the same | Hidden has a known space. Undetected does not. This changes targeting, Seek, guessing, and area effects. |
| Letting darkvision beat every stealth plan | Darkvision handles darkness. It does not defeat cover, silence, invisibility, scent masking, disguise, or misdirection by itself. |
| Forgetting Point Out | If one PC knows where a creature is, allies may still need the location shared through Point Out or clear communication. |
| Running scent as perfect radar | Scent is usually imprecise. It can locate, but it normally does not make the target observed. |
| Saying "you see nothing" when the character heard something | Name the sense. Hearing, scent, vibration, and magic can all create clues without visual observation. |
| Calling for rolls without a searched area | Seek needs a chosen area. Search in exploration covers travel differently. |
| Revealing unnoticed creatures with dramatic narration | If a creature is truly unnoticed, do not announce it with suspicious camera work. Describe clues only when a sense or check justifies them. |
| Applying flat checks after attack results | Resolve concealed or hidden targeting uncertainty before treating the attack as a hit or miss. |
GM Procedure
When a detection situation gets messy, use this table script:
- "What sense are you using?"
- "What area are you checking?"
- "What blocks or distorts that sense?"
- "What is the target's current awareness state to you?"
- "Are you Seeking, Pointing Out, guessing, using an area effect, or changing position?"
That script keeps stealth tactical without turning the GM into a fog machine with opinions.
Best Links
Use Stealth, Survival, conditions, combat stealth, checks and DCs, actions and activities, and initiative and encounter starts.
For tools, use alchemical items, consumables, adventuring gear, utility spells, and GM environment guidance.
Hot Takes
Perception is not just initiative with better branding. It is the gateway between information and action.
Scent is excellent, but it is not a thermal scope. If a player or monster has scent, say what it can locate and what it still cannot observe.
Darkvision is overrated by players and underrated by GMs. It should solve darkness, not every stealth scene in the campaign.
Point Out is the action that keeps one player's good Seek roll from becoming secret trivia.
Return to the PF2e rules guide.
