Surprise, Stealth and Initiative

Initiative
If you act much slower than the fastest character you are effectively surprised relative to it, reducing your ability to act fully on your turn during the first round of combat.

When you roll initiative, the creature with the highest results sets the Initiative DC every other combatant's initiative is compared to. If you fail a DC ten lower than the creature with the highest Initiative you gain one Stunned condition at the start of the encounter. If you fail a DC twenty lower, you gain two, and so on. ''Example: Valeros gets Initiative 34. Seoni gets Initiative 24. The bugbear gets only 23. And the three Goblins act at Initiative 2.

Seoni narrowly escapes getting Stunned. The Bugbear starts the combat Stunned 1. The goblins are all Stunned 3 each - they get to do nothing at all during the first round (and will act last during round 2).''

Surprise
Being on high alert grants a +4 bonus to Initiative.

You are assumed to be on high alert when you creep through a trap-filled corridor, or are about to bust down a door. Or when you hear an unexpected noise or otherwise perceive something suspicious.

You can only maintain high alert for short periods of time (generally no longer than one minute). You cannot be on high alert during normal patrol duty, such as when you make a routine search. If you suffer from any debilitating Conditions* you cannot be on heightened alert. (If you make a sound but then manage to evade detection for a short while, you can again hope your enemies will have come off high alert) Certain creatures can maintain high alert indefinitely.


 * ) including conditions related to death and dying (Doomed and Wounded), conditions that lower your abilities (Clumsy, Drained, Enfeebled, Fatigued, Stupefied, etc) and conditions related to your senses (Blinded, Dazzled, Deafened, etc).

Stealth
The threshold for when Stealth checks are required is high in this campaign. Just regular movement into position before a raid will usually not require any Stealth checks despite using Sneak movement, unless the targets have placed an actual sentry. Many criminals will be tired, lazy or drunk enough that no Stealth checks will be required even when you and your fellow officers move using the Sneak action.