Monday, May 16, 2016

Skyship Battles

While I designed an adventure for Calidar’s Skies of Fury, I had the opportunity to set up a possible ship-to-ship battle as one of the game’s outcomes. Skies of Fury is a promotional booklet available exclusively to the Kickstarter backers of my present main project, Beyond the Skies. This was the perfect opportunity to put some numbers on paper as regards the two vessels’ performances, and how they might relate to a hex grid.

One challenge is that Calidar is intended to use generic stats which can be fairly easily converted to your chosen RPG. I’m bringing this up because guidelines on such system-neutral game stats are included in Beyond the Skies (due out August 2016), along with extra details about ship stats and their armament. On the other hand, CAL1 In Stranger Skies, the original book in the Calidar series, delves into ship movement in a theoretical manner. This article helps clearing up a few things. Another challenge lies in how the maneuver diagram may be used with a hex grid.

First off: the stats!

Unless indicated otherwise, ratings (such as armor, abilities, defense checks, etc.) are expressed in the rules-neutral guidelines as percentages of customary ranges featured in the chosen game mechanics. For example, a Personality rating of 50 (%) would translate to a Charisma of 9 in a D&D game (50% of 18).

Structural Rating (SR): This number indicates how much damage a skyship can withstand before its enchantments fail catastrophically. At about 70% SR loss, a skyship becomes hard to maneuver and, if not in the Great Vault, starts losing altitude. A ship the size of the Star Phoenix has 120 SR, that is approximately 1 SR per foot of length (rounded up to the next ten). Subtract 20% for a clipper-style vessel (such as Alorean skyships). Add 20% for a skyship designed primarily for war rather than speed (such as Draconic vessels). Double the rating instead for a dwarven ironclad.

Armor Rating (AR): Lightweight or fragile vessels, such as rafts, river boats, canoes, longships could do with an AR10 or less. A typical wooden, multi-decked skyship, such as the Star Phoenix possesses an AR25. A dwarven ironclad could reach AR40. Magic can easily modify these ratings. If either the attacking vessel or its target is moving, up the target AR +15. If both are moving, add +30 AR to the target instead. If winds are gusting, increase the target’s AR another +5 to +20. Game referees are welcome to tweak these ratings for best results.

Movement Stats: You’ll need a copy of CAL1 to follow this. First we have the ship’s class, which addresses its maneuverability (Agood, Baverage, or Cpoor). One or two modifiers follow, which are associated with the ship’s speed (PS stands for Powered Speed, and SS for Sail Speed.) You’ll find these two in the table on page 124. I reproduced it below for convenience. In parenthesis, I then add the type of propulsion to the abbreviated stats.

Points of Sail

Skyship Origins
Sail Speed
In Irons
Kragdûr Dreadnought
50 mph
Close Hauled
Munaani Galley
20 mph
Close Reaching
Wayfarer Longship
20 mph
Beam Reaching
Lao-Kwei Junk
Broad Reaching
Draconic Warship
Alorean Clipper

The term used for the type and number of attack is TA such as 1 ballista/2 scorpions, etc. Special abilities (a vessel’s spell-like powers and other unusual effects are listed after the game stats.)

Damage & Range Ratings: The Damage Rating, or DR, from individual weapons or siege machines (catapults, ballistae, trebuchets, etc.) applies directly to a skyship’s SR. Unless noted otherwise, siege weapons require a minimum range to operate. Ranges are listed here in yards (meters). As an optional reference, common siege weapons of Calidar are listed below.
  • Scorpion: M+4 damage (300/600/900, line-of-sight trajectory at short range, otherwise parabolic; no minimum range; half-damage at medium and greater ranges)
  • Ballista: Hi+6 for (200/400/600—as scorpion)
  • Light Catapult: M+8 (200/250/400—Min. 100)
  • Heavy Catapult: Hi+10 (250/400/600—Min. 125)
  • Trebuchet: VH+12 (250/500/800—Min. 150)
  • Battering Ram: M+8 (range n/a)
  • Kragdûr Culverin: Hi+10 (200/250/400—as scorpion)
  • Kragdûr Firemouth: VH+12 (250/400/600—Min. 60)
  • Alorean Thornbush: M+4 (200/250/400—as scorpion; ensnare within razor-sharp thorns 15’ radius until burned or hacked away)
  • Alorean Podkin: M+8 (250/400/600—Min. 100; M+4 continual acid or rust damage within 20’ radius for the next 1-2 minutes or until doused or splatter surface is destroyed).
Terms used for damage are VL (very low), L (low), M (medium), Hi (High), and VH (very high), plus or minus some other modifiers. Simply assign dice (or combinations of dice) that best corresponds to these rating in the chosen game system. In Calidar parlance, L could be equated to a short sword, while H might be a two-handed sword.

If some kind of defensive check, labeled “DC,” is ever needed, use the appropriate score for the ship's captain or its helmsman, based on the chosen game system.

The last few stats include the ship’s length and flag (a colorful tagline).

Some time ago, one of the Admiral level Kickstarter backers took me up on my offer to draft deck plans privately for a fee. I’ll use tentative stats for his ship here, as a way to illustrates how its stats stack up.

The Windblade: A twin-masted Calidaran privateer, of wooden construction, it was conceptually intended for speed and, most likely, smuggling. Cpt. Tallie Baratha is in command.

The Windblade: AR 20, SR 120, Class B, PS nil, SS +1.5 (ethereal sails or seitha), TA 4 ballistae, DR Hi+6, DC as captain, Size (120’ length); Flag: Meryath privateer
Special Abilities 
Forward Winch: Mounted on a rotating platform, the forward ballista can shoot grappling hooks tethered to a large winch.

(*) AR20 expresses a value 20% of the customary range for the chosen game’s armor rating. Taking the D&D game as an example, armor class typically runs from 10 to –10, where 10 equals 1% of the range and –10 a 100%. 20% therefore would yield an AC of 6.

In Skies of Fury, the Windblade intercepts another vessel. Approximate wind direction and strength are set for the encounter (though some randomness is included). The fight can take place either in the void of Great Vault, or somewhere above the Dread Lands.

The speed of most ships in Calidar is based on wind strength adjusted for a skyship’s relative bearing. The original diagram (see earlier in this article) gives about ten bearings, which may give some pause since most combat grids use hexes. Two illustrations below show how to adapt CAL1’s sailing diagram to a hex grid.

Click on these diagrams to view a sharper image.

Map Scale:  I used a 20mph wind as an example to show how many hexes the Windblade can move, 10 mph being roughly equivalent to 1 hex per combat action. In the D&D 5th Edition and Pathfinder games, a combat action takes a round lasting 6 seconds. With other games, it can be as much as 10 seconds. I went with a hex representing 50 yards (using combat actions lasting 10 seconds). The alternative was 30 yards, but I didn’t like as much, and it almost doubles the size hex grid needed to run a battle. Some skyships can move very, very fast with strong winds. A 50 yard scale also makes weapon ranges more manageable—mostly 4-12 hexes.

Adjusting Speeds:  It is always possible for a captain to order half sails (or full sails), halving the sail speed as needed, or restoring a ship’s full movement. I would suggest that such orders take a veteran crew at least two combat actions to execute (in reality, it ought to take more time than this, unless the vessel uses magic or mechanical devices to control its sails). If the crew is green, four combat actions would be better. An average skyship crew can achieve the same in three combat actions.

Winds:  To determine the wind’s direction randomly, roll 1d12 on this diagram. The referee may alter the wind direction during a battle (roll 1d6: oddshift one arrow counter-clockwise, evenshift one arrow clockwise). Wind direction changes after all skyships have moved. If the wind has shifted, the 1d6’s score determines whether and by how much the wind’s speed changes as well (1-2. –10mph, 3-4. Same, 5-6 +10mph).

A sailing skyship finding itself “In Irons” during a maneuver ends its move right away; during the next action, the skyship drifts back (half the wind’s speed rounded down), and then changes bearing to an adjacent hex side before completing its normal move.

Turning:  CAL1 In Stranger Skies goes through more detail as regard turning, reflecting the skyship’s speed, its hull length, and ship class (Apowered vessels, Bflying galleons, or Cquad-masted high-speed vessels). Turning is explained in general terms: how much room it takes for a skyship to execute a 180 degree turn (whether a hex grid is used or not). This works in theory, but it could be made easier on a hex grid when players want to execute maneuvers less than 180 degrees.

The optional chart below expresses the same general idea, although in a much simpler way, indicating how many hexes a ship must move forward before pivoting one hex side. With this chart, ships aren’t as maneuverable as those described in CAL1 because the original distances to complete a turn were expressed in “ship lengths” (in feet) while the scale here is 50 yards per hex. So, an Alorean clipper making a 180 degree turn at high speed now requires at least 12 hexes (600 yards) instead of 1,500ft (500 yards). This chart does not take into consideration actual ship length—small price to pay, I think.

Skyship Maneuver Table
Ship Class
Sailing Speeds
3 per hex
2 per hex
1 per hex
2 per hex
1 per hex
1 every 2
1 per hex
1 every 3
1 every 4
1 every 2
1 every 4
1 every 5

Using the chart above, a galley (Class A) can still complete a U-turn on a dime at slow speed (pivot 3 hex sides in the same space), relative to what an Alorean clipper (Class C) can accomplish. Kragdûras dreadnoughts, though they are very large ships, are still ranked as Class A, because they use powered propulsion (vectored thrust, no less). Other types of vessels can be imagined, such as the Windblade’s foe, something truly lumbering which, though it uses powered propulsion, should still be a Class C (or “D” even, which I took the opportunity to add to the chart). Also bear in mind that some ships are certainly much larger than a single 50 yard hex (some of you may remember the Tian Feng which ran 150 yards long.)

Running a Battle: A simple way to get started is to follow the chosen RPG’s mechanics on group initiative, although this might not be the best approach. Ship maneuvers ought to take place simultaneously, or at least partially so. The side that won the initiative decides which vessel moves first (theirs or the foe's). If there are more than two craft involved, each sides takes turns moving one of theirs. The side with the initiative shoots first. As an alternative to this, skyships can take turns performing half moves, until all vessels involved have completed their full moves. Heroes and their foes only ever get one normal combat action while ships maneuver (at the referee’s discretion) or after they are done with their full moves. Resume the remainder of individual combat routines according to the chosen RPG’s game mechanics.

Sail speed is always modified at the end of a full move, as wind angle may likely have changed by then (sail surfaces might also have been altered). Vessels that come into contact, perhaps as the result of a boarding maneuver, come to a halt. Halted ships typically drift at half the wind speed in the wind’s direction. 3-D moves are explained in CAL1 In Stranger Skies, should these be necessary or desirable.

I’ll let your imagination do the rest.