:知覚［Free］:Perception has a number of uses, the most common of which is an opposed check versus an opponent's Stealth check to notice the opponent and avoid being surprised. If you are successful, you notice the opponent and can react accordingly. If you fail, your opponent can take a variety of actions, including sneaking past you and attacking you.Perception is also used to notice fine details in the environment. The DC to notice such details varies depending upon distance, the environment, and how noticeable the detail is. The following table gives a number of guidelines.

Detail	Perception DC
Hear the sound of battle	–10
Notice the stench of rotting garbage	–10
Detect the smell of smoke	0
Hear the details of a conversation	0
Notice a visible creature	0
Determine if food is spoiled	5
Hear the sound of a creature walking	10
Hear the details of a whispered conversation	15
Find the average concealed door	15
Hear the sound of a key being turned in a lock	20
Find the average secret door	20
Hear a bow being drawn	25
Sense a burrowing creature underneath you	25
Notice a pickpocket	Opposed by Thivery
Notice a creature using Stealth	Opposed by Stealth
Find a hidden trap	Varies by trap
Identify the powers of a potion through taste	15 + the potion's caster level

Perception Modifiers	DC Modifier
Distance to the source, object, or creature	+1/10 feet
Through a closed door	+5
Through a wall	+10/foot of thickness
Favorable conditions1	–2
Unfavorable conditions1	+2
Terrible conditions2	+5
Creature making the check is distracted	+5
Creature making the check is asleep	+10

:気配察知［Full-round］<習熟>:聞き耳を立てることで、近くの空間（例えば扉の向こう）に、どれくらいのクリーチャーがいるかを判断します。基本DCは20ですが、状況によって上下します（GM判断）。さらに、足音を忍ばせているクリーチャーがいる場合、そのクリーチャーのStealth達成値を超えなければ、数え間違います。広い空間で気配察知をした場合、30ft.以内の部屋の中にいるクリーチャーの位置をピンポイントで特定します。この場合でも、そのクリーチャーのStealth達成値を超える必要があります。