A scanned target removes the visibility penalty entirely. Sonar keeps a smaller penalty, while an unknown target stays the hardest case.
Detection helps the attacker read the fight more cleanly, while Hide Signature pushes the other way. Both skills matter twice, once for scan readability and once for hit chance.
The scan difficulty badge comes from the same attacker and defender comparison model. It tells you whether the target will feel very hard, hard, balanced, easy, or very easy to engage.
Stealth is a separate concealment state. If no living PC or NPC is inside your sonar zone when you activate it, the activation succeeds automatically. If someone is already in range, the best detector in that zone contests the attempt.
Passive detection uses the detector's sonar zone. Active detection sends a private sonar pulse that only the initiator and the initiator's group can see, but any successful reveal removes stealth globally.
Visibility state
Scanned target = no visibility penalty
Sonar target = -6 visibility penalty
Unknown target = -14 visibility penalty
Stealth and reveal checks
Stealth activation with no detector in your sonar zone = automatic success
Contested stealth activation chance = clamp(55 + 2 × (stealth score - detection score), 10, 90)
Passive reveal chance = clamp(40 + 2 × (detection score - stealth score), 10, 90)
Active reveal chance = clamp(55 + 2 × (detection score - stealth score), 10, 90)
Stealthed movement cost = 2 movement points per tile
Scan difficulty
Attack index = 60% weapon skill + 25% targeting skill + 15% detection
Defense index = 70% evasive maneuver + 30% hide signature
Difficulty badge = compare defense index against attack index
Very hard if defense is 25 points or more above attack
Hard if defense is at least 10 points above attack
Balanced if the two sides are close
Easy if defense is between 10 and 25 points below attack
Very easy if defense is more than 25 points below attack