Combat rules

Range gate

Useful distance = max(horizontal gap, vertical gap)
Attack allowed if useful distance <= weapon range and action points available >= 1
Ship size matters because the game measures edge to edge, not center to center

Hit chance

Hit chance = base chance + weapon skill bonus + sharpshooting bonus + aiming bonus - visibility penalty - hide signature penalty + invisibility bonus + weapon accuracy bonus
The result stays between the minimum and the maximum allowed by combat rules

Visibility state

Scanned target = no visibility penalty
Sonar target = -6 visibility penalty
Unknown target = -14 visibility penalty

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

Weapon scaling

Weapon precision bonus = weapon skill curve + sharpshooting bonus
Weapon damage bonus = weapon skill curve
Rolled damage = random damage from the weapon's own range
Final damage before critical hits = rolled damage × (1 + damage bonus)

Evasion and size

Evasion chance = base dodge + evasive maneuver bonus scaled by hull class + size bonus
Hull-class scaling keeps small ships slippery and large ships less agile

Critical and absorption

Critical chance = 5% + sharpshooting bonus
Critical chance is capped at 25%
Critical multiplier = 1.4 for laser, 1.6 for ballistic, 1.9 for torpedo
Shields absorb first, then the hull takes the rest

Counter selection

Counterattack allowed if the defender is still alive, still has at least 1 action point, and has a weapon in range
The chosen weapon is the usable one with the longest range

Counter resolution

A counterattack follows the same hit and damage rules as a normal attack
A counterattack cannot trigger another counterattack

Repair

Repair applied = the smaller of missing shields and the repaired amount after the skill bonus
If the module uses a percentage, the base repair comes from maximum shield × percentage
Repair never goes past what is actually missing

Enhancement

Buff strength = base aim bonus × (1 + enhancement bonus)
Buff duration = base duration × (1 + enhancement duration bonus)
A weaker buff never replaces a stronger one already active

Electronic Warfare

Success chance = base chance + attacker bonuses - defender bonuses
The result is clamped between a minimum and a maximum
Effect duration = base duration × duration factor
The attacker's bonus stretches the effect, while the defender's resistance shortens it
Movement reduction applied = the smaller of the remaining movement and the module's reduction

Skill curve

Skill bonus = cap × (level / 100)^0.72
This curve gives a strong boost at low levels and still rewards the last steps to 100

Attack XP

Attack XP difficulty = clamp(100 - hit chance, 0, 100)
Shield XP difficulty = clamp(18 + hit chance × 0.25, 18, 60)
Evasion XP difficulty = clamp(14 + hit chance × 0.18 + 6 if the shot is evaded, 16, 32)

Electronic warfare XP

EW cast difficulty = clamp(100 - success chance, 18, 100)
EW defense difficulty = clamp(success chance, 18, 100)