Thursday, July 27, 2017

Skyship Combat Mechanics VIII

Previously Posted Sections

1. Introduction
2. Wind Direction & Strength
3. Maneuvering
  3.1. Movement Rates
    3.1.1. Sailing Skyships
    3.1.2. Other Skyships
    3.1.3. Ramming Speed!

    3.1.4. Monsters
    3.1.5. Powering Through

  3.2. Maneuverability
  3.3. Turning
    3.3.1. Basic Turning Capability

    3.3.2. Tight Turns
    3.3.3. Caught In Irons
    3.3.4. Slowing Down
    3.3.5. Emergency Maneuver

  3.4. Climbing & Diving
    3.4.1. Ascending
    3.4.2. Descending
    3.4.3. Effects of Altitude
    3.4.4. Gales & Storms
  3.5. Collisions & Boarding Maneuvers

4. Combat
  4.1. Deck Weaponry
    4.1.1. Weapon Types
    4.1.2. Armor Ratings

  4.2 Hitting a Target
    4.2.1. Skyships
    4.2.2. Monsters
    4.2.3. Combat Modifiers
    4.2.4. Fighting in the Great Vault 

Odin's Eye is the "Space Vikings'" answer to Starfolk meddling in Calidar
4.3. Damage

4.3.1. Structural Rating (SR):  Most role-playing games use statistics to measure how much damage a target can sustain.  In the mechanics devised here, skyships have a structural rating.  This number indicates how much damage a skyship can withstand before its enchantments fails catastrophically.  Damage from siege weapons is subtracted directly from this number.  Table 8 gives damage ratings for each of the weapons.  At 100%, the ship is a wreck; its enchantments fail, and the vessel plummets uncontrollably to its doom. The same mechanics apply to a monster’s “life points.”

A ship like the Star Phoenix, a tri-masted galleon, has 120 SR, or approximately 1 SR per foot of length (rounded up to the next ten). Subtract 20% for an elven-style clipper.  Add 20% for a skyship designed primarily for war rather than speed (such as draconic vessels).  Double the rating for a dwarven ironclad.  Cards are provided which suggest SR ratings for both ships and monsters.

Monsters:  Conversion will be required to introduce your own creatures.  Most role-playing games give a life point rating to creatures.  The best method is to establish an appropriate range of life points in the chosen RPG (one single range including at the low end the weakest monster in the book with minimum life points, and at the top end the toughest one with maximum life points).  Use common sense when establishing a base range for creatures (see CC1 pg. 8 for more details on establishing a practical range).  Give them maximum life points, and convert their individual ratings to a range 1-100, which is what is used here.

For example:  If a monster had 80 life points, and the chosen RPG range of life points were 1-160, the monster’s SR would therefore be 50 (80 DIVIDED BY 160 MULTIPLIED BY 100 EQUALS 50).  If the RPG range were 1-300, the monster SR would be 26 (or 30, rounding up to the next 10).

4.3.2. Damage Location & Effects:  Combat damage applies directly to a target’s SR. Monsters' SR are listed on their individual cards in the event conversion of their original RPG’s statistics is unwanted.  Damage is rated as follows: VL (VERY LOW) such as a dagger, Lo (LOW) like a short sword, M (MEDIUM) a long sword, Hi (HIGH) a two-handed sword, and VH (VERY HIGH) an oversized weapon.  2M means double M damage, M+2 means M damage +2, etc.  As described in CC1“Beyond the Skies,” each “+” can be interpreted as a +10% bonus depending on the chosen RPG's combat mechanics.

Damage Location: For skyships in particular, locating damage may be of interest—if not for a specific effect, at least for the sake of storytelling.  Flying vessels are divided into three approximately relevant areas (roll 1d6): 1-2. Fore, 3-4. Midship, and 5-6. Aft.  In the cases when the only visible part of a skyship is its prow or its stern, then damage always applies fore or aft, as appropriate, especially with line-of-sight weapons.  If the entire length of the vessel is visible, then any of the three areas may be hit.

Once a damage area has been determined, a more specific effect is in order.  Table 9 helps pinpoint damage location within the appropriate section.  If the target is an aerostat (see 5.2.1. Dirigibles & Aeroliths), roll on the first column.  If the target isn’t a dirigible and has masts, roll on the second column, otherwise, roll on the third.  Projectiles on a line-of-sight trajectory only affect the side from which they were shot.  Unless a swooping vessel crashes through another’s masts, a ship’s ram only inflicts hull damage.  Use common sense.

(*) For example:  A trebuchet’s “+” modifier is +12, vs. +4 for a scorpion.  For gnomish battle-rods, add their +2 modifier as many times as shots were fired (see Table 8).

Damaged Masts & Sails:  If half of more of a vessel’s masts are damaged or destroyed, halve its initial MV.  If all masts in a single row are destroyed, that vessel is crippled and cannot maneuver.  If only one row of masts is left standing, the vessel becomes unstable enough that its deck weapons cannot be aimed, and it is immediately at risk of rolling over, possibly dumping overboard unsecured crew and weapons until remaining sails are dropped; loose cargo could also inflict another 3M+3 internal damage to the ship’s remaining SR.

Decimated Crew:  Skyships can function with minimal crew, but this comes with limitations.  If a quarter or more of a crew is killed or disabled, deck weapons sustain a –10% penalty to hit, –20% if half, or –30% if three quarters, because ranks are depleted enough that weapons are operated with fewer crew or untrained sailors.  If half or more of the crew is missing (killed or disabled), hoisting sails takes a full Battle Round (see 3.3.4. Slowing Down).  If a quarter or more of a crew is missing, the vessel incurs a +2 penalty to initiative during the upcoming Phase A4 (see 4.4. Combat Sequence), +4 if half, or +6 if three quarters.  Assume that 2/3 of casualties include disabled airmen (as opposed to killed outright), who are therefore out of action for the remainder of the battle.

Hull Damage:  At about 70% SR loss, a skyship is hard to maneuver—either change the ship to a less forgiving Class or assess a large penalty to piloting skills.  Furthermore, if not in the Great Vault, this skyship loses 1 altitude level per Battle Round; it cannot climb, but it can increase its descent rate to 2 levels.  At 100%, a ship is wrecked; its enchantments fail, and the vessel plummets uncontrollably to its doom.  A critical hit (as appropriate to one’s RPG of choice) typically wreaks double damage; as an option when scored against a hull or engine location, internal damage may occur instead, resulting either in a fire or damage inflicted to an internal engine (if any—roll on Table 4 with a +4 modifier; see 3.1.3. Ramming Speed).

Pinpoint Shots:  If an attack roll exceeds its attack score by 15 or more, the attacker can pick which area is actually hit (fore, midship, or aft, when visible), rather than rolling randomly.  If the attack roll exceeds its attack score by 30 or more, the attacker selects exactly what is hit (which mast, which deck weapon, what part of the hull may be breached, or whether crew is targeted—the commander cannot be deliberately selected).  Pinpointing targets with salvaged starfolk weapons isn’t possible because of the users’ inexperience with alien technology.  Monsters performing physical attacks on a skyship can pinpoint damage at will and without penalty.

4.3.3. Boarding Attacks:  The crew on one ship leaps aboard another (see 3.5. Collisions & Boarding Maneuvers). Tally the two crews, establish a combat ratio of one versus the other, and look up the result on Table 10.  The alternative to this process is to run the battle using the chosen role-playing game’s combat mechanics; this may be needed if individual heroes are involved.  When calculating combat ratios, fractions are rounded in favor of the defender.  Boarding attacks may take multiple Battle Rounds to resolve.  Casualties are not assessed until one side retreats or the other surrenders.  The attacker, however, always has the option of breaking off and retreating at the beginning of a Battle Phase (see 4.4. Combat Sequence).

Locked:  Roll again with the same odds during the next Battle Phase (see 4.4. Combat Sequence).
=>:  Roll again immediately, shifting one column to the right.
<=:  Roll again immediately, shifting one column to the left
B:  Boarding Party              D: Defending Crew
L: Light Casualties (10%)   M: Medium Casualties (20%)
                                        H: Heavy Casualties (40%)
R: Retreats                        S: Surrenders

Retreats:  The boarding party retreats to their ship; defenders may counter-attack.  The defending side must announce right away whether a counter-attack takes place.  If it does, the two sides are locked in melee until the next Battle Phase (see 4.4. Combat Sequence).  The defenders become the new boarding party, and vice-versa.  Check for commander casualties before resuming the fight (see later in this section).  It takes a full Battle Round to separate ships involved in a boarding maneuver.

Crew Experience: Subtract defending crew’s experience from boarding party’s, where 10% increments = +/–2 point modifiers to the die roll (see 4.2.3. Combat Modifiers).

Leadership Quality:  Charismatic commanders on either side are components of victory or defeat (see 4.2.3. Combat Modifiers, Commander Skills).  An “excellent” commander allows a +2 bonus to the die roll on Table 10, +1 if “good,” a –1 penalty if “mediocre,” and a –2 penalty if “poor.”  Add this modifier to the die roll for the boarding party’s commander; subtract the defending commander’s modifier.  The presence of an epic hero aboard adds another +1 bonus (or –1 if defending).  The presence of one or more adventurers (player characters) adds another +1 bonus (or –1 if defending).  Though player characters ought to be handled with traditional RPG mechanics, the rest of the battle can be run using the rules suggested here.

Example: An elite crew of 50 boards another vessel with a crew of 75.  The combat ratio is 2-3 in favor of the defending crew.  On the other hand, die rolls receive a +4 modifier due to the difference in crew experience.  First roll is a 2, resulting in a locked melee.  The boarding attack continue to the next Battle Phase (see 4.4. Combat Sequence).  The next roll is a 6, resulting in an immediate reroll, using the adjacent column to left.  The final roll is a 7: BLDMS.  The attackers sustain light casualties (5 killed or disabled) vs. the defenders who surrender after suffering medium losses (15 killed or disabled).

Commander Casualties:  The number of casualties on either side is the percent chance a ship’s commander is killed or disabled (up to a maximum of 95%)  In the previous example, the odds are 5% for the boarding party’s officer, vs. 15% for the defending captain.

Monstrous Crews:  If one or both crews are monsters with different life points, substitute the total life points of crew to the number of people.  For example, 100 crew with 10 life points each facing a boarding party of 60 with 25 life points each would result in a combat ratio 3-2 in the boarding party’s favor.  Casualties are assessed on this basis as well.

4.3.4. Area of Effect Attacks:  Some monsters and certain skyships fitted with special weapons can perform attacks that affect an area rather than a specific location.  The easiest approach is to apply the effects as described in the chosen RPG mechanics.  Scale issues will came into play as spells and other magical effects aren’t likely to affect a whole hex (100ft. scale) or even an entire skyship.  Use you best judgement to adjudicate mechanics.

4.3.5. Fire Damage:  After a fire-based attack succeeds, fire has a chance to keep burning.  Roll 1d6: on a roll of 1-2, the fire catches and starts spreading.  The crew may attempt to put out the fire during Battle Phases C2 and F2 (see 4.4. Combat Sequence).  It succeeds with a roll of 1-2 on a d6.  A crew locked in a melee (see 4.3.3. Boarding Attacks) cannot put out fires.  Deck weapons cannot be used while the crew is busy fighting fires.  If an existing fire is not put out, it causes the same amount of damage at end of Phases C2 and F2 as was inflicted initially.

4.3.6. Swarm Attacks:  Large monsters (Class C and D) have a chance of defeating a warship on their own.  Smaller, isolated monsters (Class A and B) realistically do not, however, unless they have access to relevant magic.  It may be best to have smaller monsters attack as a single swarm.  This type of attack takes place in the target’s hex.  For each monster in a swarm, add a +3% bonus to hit (see 4.2. Hitting a Target) and +1 extra damage per attack (see 4.3.2. Damage Location & Effects).  For example, a pack of 10 griffons would fight as a single griffon but with a +30% bonus to hit and +10 extra damage per attack.  Not all monsters in a swarm attack at once; many are flying around, dodging projectiles, or missing their own attacks entirely, thus the single attack roll with modifiers.  Use the monster’s AR for the swarm as a whole (see 4.1.2 Armor Rating).  Add up all their life points (see 4.3.1. Monsters)—this is becomes the swarm’s SR.  A swarm sustaining 50% or more damage typically flees, or it loses half its modifiers.

When swarmed, the crew on an open-deck vessel is considered locked in melee (see 4.3.3. Boarding Attacks).  It is possible for a skyship within range of a swarmed vessel to shoot at these monsters, deliberately taking the risk of hitting their quarry instead.  Any missed attack roll must be rerolled and checked against the swarmed vessel’s AR.

4.3.7. Proportional Damage:  This refers to the ability of a target to reduce damage based on how tough its armor is vs. how effective an attack is.  Guidelines provided here are entirely optional.  Any time a modified attack roll exceeds the target’s hit score by 25 or more, full damage applies (other effects described in Table 9 always apply without alteration).  If the attack succeeds by less than 25, apply only half the damage, rounded up.  Using a scale of 1-20 for hit scores, this 25 point margin equals +5.  For example: if a hit score of 12 is needed, rolling a 17 would qualify for full damage.  As another option, critical hits (unmodified attack rolls of 95 or higher) inflict double damage, although proportional damage mechanics can still apply, as appropriate.

If a more detailed approach is wanted, ignore the simple guidelines given above, and use instead Table 11.  Cross reference the target’s armor rating with the column showing by how much the attack roll exceeded the hit score.  All other effects described in Table 9 still apply without alteration.

For example:  A light catapult attack needed a hit score of 70 to succeed against a dragon.  The attack roll was 83 (less than 20 over).  Cross reference the +11-20 column with the target’s AR of 35.  The catapult’s damage of M+8 should be reduced 1/3 when rolled.  However, the result for deck weapons with M-rated damage should be shifted one row up, yielding instead a –¼ result.  Damage is then rolled, and the total reduced by a quarter.  If the weapon had been a trebuchet, its VH-rating would shift 3 rows up, yielding instead a full damage result.

These mechanics favor heavier weapons vs. lighter ones, while reflecting attack rolls vs. armor ratings more accurately.  On the other hand, a ballista can shoot twice per Battle Round, compared with a light catapult shooting once per round, or a heavy catapult only once every 2 rounds.  Table 11 gives heavier weapons a better chance of delivering full damage.

Design Note:  If these mechanics are popular, current damage ratings of deck weapons will need to be revised (especially the ballista and the scorpion, down to M+6 and Lo+4 respectively).  This certainly improves the survivability of a lone monster against broadsides and player characters acting together during its approach.  On the other hand, this will slow down a game and make life much harder for math-challenged players.  So, Dear Readers, time has come once again for you to chime in!  Your opinions are wanted on this matter. 


4.3.8. Defense Checks (DC):  Defense checks emulate a routine common to role-playing games, which allows a die roll to prevent or reduce damage from an attack, especially magical.  Either use the appropriate RPG mechanics whenever possible, or assume a basic 50% chance for a skyship or a monster to succeed a DC.  A number of factors can help/hamper success, such as the target vessel’s commander skill (see 4.2.3.) and what was targeted.  Table 12 suggests percentile scores to match or exceed for specific targeted materials.

Materials:  Ordinary canvas is thick, non-magical fabric.  Enchanted sails are those used to catch ethereal winds in the Great Vault; this fabric receives various protective dweomers making it more resistant to wear and tear as well as various types of damage.  Giant spider silk typically receives some magical refinements; it is much stronger than ordinary canvas or hemp.  Unprotected wood refers to hull construction material mostly; though it carries the necessary enchantment providing lift, it does not often include other protective magic.  Metal sheathing is a thin layer of metal, usually copper, covering certain skyships’ hulls.  Metal armor is commonly used on dwarven ironclads and alien vessels.  Dragon scales may protect a wooden hull (especially on vessels of the Draconic knights) against a specific type of damage, and slightly increase AR (+5).  Dragons always succeed their DC against attacks of the same type as their breaths, so do their scales when affixed to skyships.  However, skyships aren’t dragons and are, therefore, remain subject to critical failures, thus the DC 5 listed in Table 12.

Types of Attack:  Acid attacks include corrosive gases.  Dragon breaths are the stuff of fantasy and magic, and therefore function all the same on a planet and in the Great Vault’s airless void.  Some skyships may be fitted with these sorts of attacks.  Cold, electrical, fire, and rust attacks are self-explanatory.  Entropy is a form or attack ranging from rot to ageing; it and rust are most prevalent with undead creatures and possibly with sustained exposure to netherworld conditions as well.  Anything else, especially alien weapons, can fit under “other” if no outlandish effects are described.

©2017 Bruce A. Heard. All Rights Reserved.

  4.4. Combat Sequence

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