Macro Combat Rules in D&DEdit
ForewordEdit
The purpose of this sandbox is for me to gradually flesh out workable rules for large scale combat, including simple vehicle combat scenarios to full scale war and destruction. If this will ever be taken to relative completion, I might make a sourcebook out of it.
Ship to Ship, Vehicle to VehicleEdit
Whether on sea, in the air, on land or even in outer space, battles between vehicles and ships are different from a fight between player characters and monsters. Combat that pits ships and vehicles against each other often occurs at a much longer range, as their weapons are faster, deadlier and less bound by infantry convention. The speed and maneuverability of the vehicles in question and the level of armaments they can carry is vastly different, and in very large vehicles, external and logistical factors may influence response time. Battles between vehicles occur on a larger scale and are therefore referred to in this work under ‘macro combat’, but at the same time there needs to be a degree of transparency between macro combat and normal combat (player characters against monsters), as the two can overlap.
For instance, a naval battle draws to its conclusion, as the two flag ships of opposing fleets broad-side each other and unload their cannons into the other’s hull. In the mean time, archers and spellcasters are flinging projectiles back and forth on deck. A well placed fireball fells the main mast and incinerates the ship’s sail, while a stray cannon shot blasts a group of enemy archers flailing into the air.
This example of ship to ship combat requires several different layers of interaction. While ships are more durable and their weapons are more powerful, they must be able to interact with player characters without killing them instantly. Similarly, the players should have the ability to put up a decent fight against the ships without becoming overwhelmed. While governing the mechanics of combat between two similar entities - character against monster, vehicle against vehicle, or even army against army - is relatively simple, pitting two fundamentally different things against each other will require the integration of different mechanics. This difficulty presents itself especially when dealing with large ships, which can be part of the setting for a battle as well a combatant in it.
Vehicle BasicsEdit
Vehicles are treated as constructs for the purpose of giving them D&D-compliant statistics. They have an Armor Class and ability scores, although no Constitution score. Vehicles have no Intelligence score unless they have an autonomous on-board intelligence (such as an AI that controls ship systems either in lieu of or in concordance with the existing vehicle crew).
While certain vehicles may be able to function autonomously to a degree (like state of the art space worthy vessels or advanced aircraft), a vehicle’s effectiveness in combat depends largely on the skill of its pilot and the crew responsible for operating its subsystems.
Vehicles and Macro Combat Hit PointsEdit
Vehicles have macro combat hit points (abbreviated mhp). These are not to be confused with their normal hit points. INSERT RULES FOR ASSIGNING MHP TOTALS TO VEHICLES HERE. A vehicle reduced to 0 mhp can no longer function as such and is effectively ‘dead’.
Example: Let’s take a rowboat. A rowboat can seat a meager handful of people and is propelled by oars or a single sail. It has little speed or armaments to speak of and is roughly 10 to 15 feet long, making it a Large-sized vehicle. Let’s be generous and give the rowboat 2 mhp.
Example: Now let’s take a bigger boat, like a caravel; a relatively compact and highly maneuverable two-master sailing ship used for exploration and transport. They average at about 80 feet of bow length, making them a perfect example of a Colossal-sized vehicle. At the very least, it is worthy of being called a ship. Let’s give the caravel 20 mhp.
Vehicles and Macro DamageEdit
There is a distinct difference between killing a monster and destroying a vehicle. Vehicles may be robust, but if you hit them in key areas, or if you damage something particularly integral to the vehicle’s operation, it ceases to operate. Rip out the trans axle on your car, or reduce a boat to flotsam and jetsam and it is effectively ‘destroyed’. It no longer operates as a vehicle does and while its superstructure may still be partially intact, it is effectively rendered inoperable. In order to make a game of D&D more dynamic, such details have been waived in fights between PCs and monsters, where a creature takes damage until it goes in the negative figures and goes down.
Vehicle weapons deal ‘macro damage’. This damage translates to mhp on a one-to-one basis. A cannon blast that deals 3 macro damage subtracts 3 mhp from a targeted vehicle’s total macro combat hit points.
Normal Damage to Macro DamageEdit
The amount of damage a vehicle can take depends on its construction and size. While a man with an axe might make relatively quick work of the aforementioned rowboat, it’ll take him quite a while of chopping to do any real damage to the caravel. As a general rule, it requires 10 points of damage to deal one point of macro damage to a vehicle, plus 5 points for every size category larger the Vehicle is, or minus 2 points for every size category that it is smaller (to a minimum of 1 point of damage for 1 point of macro damage). Double that amount or more will do 2 macro damage, three times that amount or more does 3 macro damage, and so forth.
A vehicle is immune to normal damage; any attack too weak to deal at least 1 point of macro damage is ineffective.
If a creature attacks a vehicle with a weapon that is very effective against the vehicle’s construction, its size category is treated as one larger for the purpose of damaging the vehicle. Examples of this are axes and fire effects for wood, armor piercing weapons for armored vehicles, heavy blunt weapons like a sledgehammer for lightly armored steel vehicles, etcetera.
Example: The man with the axe (Medium size) is angry with the rowboat (Large size) for some reason. Maybe he stubbed his toe on it. It’s common knowledge though that wood is pretty vulnerable to axes, so he (effectively Large size) would need to deal 10 or more damage on his attack to inflict one point of macro damage to the rowboat, but for 1 macro damage to the caravel he would need to deal at least 25 damage, and for that same amount of damage he would do 2 macro damage to the rowboat, reducing it to rubble.
Example: Godzilla (Colossal+ size) stomps on a 5 mhp car (Large size). The beast deals 1 macro damage per 2 normal damage, and therefore easily crushes the car underfoot. The end.
Macro Damage to Normal DamageEdit
If a weapon that deals macro damage hits a creature however, every point of macro damage deals 2d10 normal damage of the appropriate type to anything directly hit, or 1d10 damage if a creature is caught within the blast radius. For example, a normal cannon that deals 1d4 macro damage on hit deals (1d4)d10 shrapnel damage to any creature within 10 feet of the impact point, usually allowing a Reflex save for half damage.
Remark: Normally, heavy vehicle weapons shouldn’t directly target creatures. This measure is taken so your 10th level rogue doesn’t suffer a direct hit worth (2d4)2d10 damage from a weapon designed to target other vehicles. This restriction does not necessarily apply to NPCs or fodder characters, though, so it does not prevent DMs from having a laugh with this. Targeting particular squares (or cubes) however is possible, allowing a vehicle to target its weapon like an area effect spell; (2d4)d10 damage, Reflex half is a lot less overwhelming.
Remark: Certain special personal weapons may deal macro damage. An RPG missile launcher designed for use by a soldier may deal 2d4 macro damage against vehicles or sufficiently large objects. If used against creatures, that same weapon would likely deal (2d4)d10 damage in a 15-foot radius burst, allowing a Reflex save for half damage.
