Naval combat

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  • The amount of damage is determined by the firing Sea Attack value, multiplied by the firing Ship’s Strength (i.e. reduced by Strength losses), and then divided by the target’s Hull value.
  • There is also a chance of a Critical Hit, which could quickly and dramatically damage a Ship’s Organisation or Strength. Default Critical Hit chance is 10% and default damage multiplier is 10x (defined in defines.lua file).

Stacking Penalty

A fleet has a 4% penalty to Positioning per combined Hull above 16 (TFH). This penalty not only makes it harder for a fleet to hit the enemy, but also increases the chances of friendly fire. The penalty is reduced by 10% for each point of a commander's skill.

Surprise Attack

Submarines and Naval Bombers have a chance of surprising the enemy.

  • Naval Bombers: 25% chance, +75 attack
  • Submarines: 50% chance, +300% attack

The surprise effect lasts three hours.


There is up to a 33% penalty for insufficient screens i.e. not enough DD and/or CL. You need at least one screen per capital ship to avoid this penalty

Night and Weather

There are significant penalties for actions at night and in bad weather. The night penalties can be reduced through researching technologies such as radar.