Naval Combat Rules

Naval Combat Rules

These rules are more of guidelines than anything hard and fast.

Basic Rules

  • Combat is in two phases, each with its own map - one is for open water, with each ship having a token that moves and maneuvers. On this, each ship acts on one initiative. The other is the ships themselves, standard DnD scale, with standard DND combat.
  • Basic actions the ship can take:
    • Change speed
    • turn
    • fire
    • drop anchor.

One person (the captain) decides these, but each person assigned to that part of the ship determines how effective it is. IE, the captain calls to change speed or turn, the player at the helm (usually, but not always the captain), rolls vehicles (water). The captain calls to fire the main guns, the player at those guns rolls to attack.

  • Turning is not instantaneous -
    • a large ship takes half its movement to turn 30 degrees
    • A medium ship half movement for 45
    • A small ship half for 90.
  • Movement speed is determined by mast setting -
    • Full, 3/4, 1/2, 1/4, full stop.
  • Ship size determines how fast a ship can accelerate
    • A small ship can set its speed each round
    • A medium ship can change two steps up or down
    • A large ship can change one.

Spotting Mechanics

Each Ship has a detection range from which it can be spotted on the horizon.

  • Tiny Ship: 5 KM
  • Small Ship: 10 KM
  • Medium Ship : 15 KM
  • Large Ship 20 KM
  • Huge Ship 25 KM
  • Gargantuan Ship 30 KM

If a ship is closer than its detection range to the players or vice versa its considered "spotted" and its presence and whereabouts are known.

Detection can be obscured by weather conditions or fog. Detection depends on line of sight, if line of sight is interrupted so is detection.

Firing Mechanics

Cannon accuracy follows a linear probability to hit curve based on range with 100% chance to hit at point blank and near 0% chance to hit at max range. D100 will be rolled for attack rolls. Ship size that you are attacking modifies percent to hit chance.

The Chance to hit is based on the following equation:

\begin{equation} Chance to hit = ((100 - [100/Max Range]*Range) * Size Modifier) * (Character Skill Mod) \end{equation}

Size Modifiers:

  • Tiny Ship: 0.5
  • Small Ship: 0.75
  • Medium Ship : 1
  • Large Ship 1.25
  • Huge Ship 1.5
  • Gargantuan Ship 1.75

Character Skill Mod is Based on Standard D20 + or - Stat:
+0 = 1.0
+1 = 1.05
+2 = 1.1
+3 = 1.15
+4 = 1.2
+5 = 1.25
+6 = 1.3
+7 = 1.35
+8 = 1.4
+9 = 1.45
+10 = 1.5

Chance to Hit Calculator

If a hit is successful damage is rolled. In order for a hit to actually do damage the rolled damage must exceed the ships damage threshold. Highly armored ships will have high damage thresholds. Damage below the threshold counts as zero damage.

Basic Sample Ship Stats

Hp: 100
AC: 15
Speed: 8 knots
Damage threshold: 10


The Gus

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