[EXPLORATION]
You attempt to avoid notice while stealthily traveling at half speed. The GM rolls your Stealth check in secret and compares the result to the Perception DC of any creature that may notice you as you travel.
Success You're undetected by the creature and are also typically unnoticed by the creature.
Failure The creature takes notice of your presence. You lose the unnoticed condition if you had it.
Creatures that notice you during exploration can lead to different outcomes. If hostile creatures notice you, an encounter is likely to start as a response.
If you're Avoiding Notice at the start of an encounter, you can choose to use Stealth for initiative instead of Perception. If you do this, the GM makes a new secret Stealth check for you. After using the result to resolve initiative, the same Stealth check result is used against enemies with the outcomes described by the Sneak action. If you would be ineligible to take the hide action, the result is always a critical failure.
Creatures that are Refocusing, Searching, Investigating, Treating Wounds, Repairing, Detecting Magic, Identifying Magic, Repeating a Spell, Following the Expert, Hustling, Cover Tracks, or busy with another activity that has their full attention away from a potential threat, are considered Distracted when engaged by undetected or hidden hostile creatures. Characters who are Aiding another character who is engaged in an action that would make the Distracted. The same applies to creatures who are the target of a Ready action from an undetected hostile creature. Distracted creatures suffer a -4 circumstance penalty to Perception checks and initiative rolls and can only use Perception for initiative rolls.
The following actions never distract you: Avoid Notice, Defend, Scout, and Track.
<aside> 💡 Why the Change? This rule does not exist in Player Core, but it has been frequently used in multiple Adventure Paths as a result of a successful ambush. This rule expands the definition and integrates that logic back into core options available to players.
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You can Ready a single ◆ action before initiative is rolled (usually a Stride, Strike, or Interact, but the GM can allow single action feats such as Flurry of Blows, Lunge or Quick Draw). You can trigger that Readied action before the initiative is rolled if you are Undetected or Hidden from the hostile target, or you are Observed but the target do not expect imminent aggression from you.
Creatures attacked out of initiative with a Readied action are considered Surprised. When a creature is Surprised, it is off-guard to the attack and suffers a -4 circumstance penalty to initiative and can only use Perception for initiative rolls.
Any of your allies can also Ready an action, as long as there's enough time and preparation, such as communicating the plan of an ambush for at least 1 minute. However, once you trigger your Ready action and initiative is rolled, only allies that have initiative order equal to or higher than the Surprised creatures can use their Ready actions before combat starts normally.
The reactions happen simultaneously in the order of your choice. After all reactions resolve, combat starts and all players and opponents act in order of initiative.
<aside> 💡 Why the Change? Without a tactical option to prepare an ambush and benefit from it, the game discourages careful tactical play and ignores real life situations where one side has a clear benefit from preparation. However, Surprise has been carefully balanced not to give too much of an advantage such in other games (Dungeons & Dragons, etc.). Typically the party will only benefit from a single ◆ action before initiative is rolled.
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Typically, Ready an action is not a Subtle action and telegraphs intent. While it doesn’t matter for the purpose of Surprise as typically the target needs to treat you as Undetected or Hidden or incapable of planning an attack, it may be obvious to creatures that Observe you can tell you are preparing to do something as a reaction in the spark of a moment. The DM may allow a Deception check against the highest among the Perception DC of all Observing creatures to hide your intent in innocuous activity but this makes any check as part of the Readied action with a -2 circumstance penalty.
<aside> 💡 Why the Change? Being seen preparing an ambush is only important in social environment in certain campaigns. Still, it is an option with a benefit and downside (particularly for Strike) that allows to hide your intent from Observing creatures that may Point Out to the target and foil the ambush attempt.
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