So, combat. If there's one criticism of D&D combat, it's that it can get a little mechanical and repetitive. A lot of the onus for that falls on the DM and the players, but it's an easy rut to fall into, especially a few hours into a long game session. I'd like to develop something that makes the basic mechanics of D&D combat a little more dynamic, and takes it away from the endless loop of roll-to-hit/roll-damage.
The first thing I need to do is lay out the kinds of things I want to achieve. I have three main goals here: create something concrete for critical fumbles, make critical hits a bit more interesting, and introduce the possibility of permanent injury to characters dropped below zero hit points.
The combat system I'm using as the base here is 3rd edition: the attacker rolls 1d20, adds his attack bonus, and that's the Armor Class struck. It's simple, it works about the same mathematically as earlier editions, and above all it's dead simple to explain to new players. I have no problem with descending ACs and THAC0, but I've played with countless people who could never figure it out. In 3rd edition, I've never had to stop in the middle of combat to tell a player what AC he hit, and it's not an aspect of the game that I miss.
The first thing I want to change from 3rd edition is the expanded critical hit range for certain weapons (i.e. a scimitar doing a critical on a roll of 18-20). In my game, a critical hit is rolled on a natural 20. I'm also doing away with the confirmation roll: there's little more disappointing than rolling a 20, then missing on the roll to confirm. I will have a secondary roll, but it's going to determine some other stuff; once a critical has been hit, a critical it will remain. (I've never been quite sure of the purpose of the confirmation roll, though I've heard it explained as getting around the problem of monsters that need a 20 to hit always doing a critical. It's not a problem I particularly care about.)
(I may keep the expanded criticals in if I retain Feats in the game, and use the range in the equipment lists as the maximum amount that the weapon can be expanded to. If a guy wants to burn two Feats so his scimitar can critical on a roll of 18+, he's more than welcome to do it.)
As far as damage on a critical goes, I prefer rolling extra dice rather than going for a flat multiplier. I'm torn on whether to apply damage bonuses once, or to each die. At the moment, I'll keep it conservative: for a standard critical you roll the weapon's damage dice twice, and add your damage bonus after. And although I said that I was being conservative, I want to add the possibility of infinitely scaling damage: basically, if the dice roll well enough, there's no limit to the total damage that can be dealt. Player's love doing astronomical amounts of damage, and I happen to enjoy making my players happy. Besides, the monsters will be doing it as well, and I also love making my players sad.
And now to weapon and armour breakage. Breaking weapons and armour in D&D is quite rare, and at least in 3rd edition it's something the player has to do in lieu of dealing damage. I'd like it to happen in the course of regular combat, and to be honest I just like the imagery of a guy blasting through his opponent's shield and smashing the arm behind it. That's the sort of thing that ought to happen on a critical, and I want to put it in there. I also want the possibility of a player hitting his opponent so hard that he breaks his own weapon. I've read accounts of ancient warriors pausing in the middle of battles to straighten their swords with their feet, and while those were bronze weapons, and the PCs will most probably be wielding iron and steel, I want to include something along those lines.
This is where the secondary roll comes in: not to "confirm the critical" as it does in 3rd edition, but to determine if the critical has any secondary effects. Here's a preliminary table:
|1||Your own weapon breaks (if possible)|
|2||You are disadvantaged in the next round|
|16||You deal a debilitating wound|
|17||You damage your opponent's armour (if possible)|
|18||You damage your opponent's shield (if possible)|
|19||You break your opponent's weapon (if possible)|
|20||Add an extra dice of damage, and roll again|
Note the multiple times that "if possible" appears. This is to stop magical weapons being broken by normal ones. Basically, normal weapons can break or be broken by normal weapons. A +1 weapon can break any normal weapon, and another +1 weapon, but it can't be broken by a normal weapon. And so on: a magical weapon can only be broken by a weapon of equal magic, and can only break upon armour of an equal value. I need to do more thinking about how this system interacts with monsters that use natural weapons and armour, but that's always a problem with D&D rules focused on arms and armour.
Being "disadvantaged" above means that you may have gotten your weapon stuck, or overbalanced yourself. I would play it as the PC being able to make half the usual number of actions in the next round, and suffering a penalty to hit and AC (perhaps a simple -1, or maybe the Disadvantage rule from 5th edition, which involves the player rolling twice and taking the lesser value.)
A debilitating wound is something that makes it harder for the victim to fight: blood in the eyes perhaps, or an injured leg. I'd simply play it as a penalty on all actions (-1 to all rolls, or 5e disadvantage as described above).
Damage to armour and shields would probably result in destruction in the case of a shield, and the reduction of AC bonus by 1 in the case of armour.
My players always ask me to describe some misfortune that befalls them when they roll a natural 1 to attack. 3rd edition, at least in the core game, has no system for this, so I usually just toss something out that has no actual effect on gameplay. I'm going to create a chart, like the one above, to throw in some effects.
|1||You break weapon your own weapon (if possible)|
|2||You drop your weapon|
|3||You are disadvantaged next round|
|4||You deal yourself some damage|
|5||You damage an ally (if possible)|
There's nothing too startling there, just the usual things that players expect on a fumble. Being "disadvantaged" here means much the same as it did in the critical hit chart above. Dealing damage to yourself is a possibility I've included, but I certainly won't have it as a full damage roll from your own weapon, or anything so ridiculous. It might just be a flat die roll of 1d4, to represent a sprained ankle or something similar. Damaging an ally is always fun, but I've added the "if possible" stipulation to head off particularly silly instances. I've also left a substantial range for No effect, because I don't want to be dealing with this stuff every single time someone fumbles. Sometimes an automatic miss can be penalty enough.
Characters spend a lot of time in D&D being hit with swords, but outside of death they rarely suffer any negative side-effects. I want to introduce the possibility for a character to receive a permanent injury when reduced to negative hit points. It won't happen every time: I will probably have it as a percentage chance based on how far below 0 the character went when felled. If he goes to -1, there's a 5% chance, at -2 a 10% chance, and so on.
|1-10||Extra bleeding (character loses 2 hp per round while bleeding)|
|11-15||Extra bleeding (character loses 3 hp per round while bleeding)|
|16||Severed hand or foot (75% chance hand, 25% chance foot)|
|17||Severed limb (25% chance each arm, 25% chance each leg)|
|18||Broken bone (arm, leg, ribs, cracked skull)|
You may have gathered that this one is really in the preliminary stages, as I haven't worked out the mechanical effects of severed body parts and broken bones (besides the obvious ones). Receiving an impressive or disfiguring scar will influence how NPCs react to the character in certain situations, and either could be detrimental or beneficial.
One thing I don't want this system to produce, though, is a party of permanently crippled characters. I need to figure out which spells can heal these effects. The extra bleeding effects will be healed by a simple cure light wounds spell, or even by bandaging. A severed hand or foot I would allow to be reattached with a cure serious wounds, provided that said extremity is available to press to the stump. I'd let the same spell fix broken bones. A severed limb I might make more difficult to deal with: maybe cure critical wounds? The scars I would have completely healed by any cure spell; those would only come into effect in the case of natural healing.
Gutting It Out
Finally, I want rules for PCs who just refuse to go down. At the player's option, I will allow any PC to make an attempt to keep fighting by making a Will save of DC 15 + the number of hp below 0 that the character currently has. For example, a character at -1 would have a save DC of 16, and a character at -9 would have a save DC of 24. This save must be made every round, using the character's current hit point total, and as soon as it is failed he will fall unconscious. Once unconscious, no further attempts can be made.
Any character attempting to "gut it out" has to check for the possibility of permanent wounds first. That character will bleed at twice the normal rate: 2 hp/round for most characters, but as much as 4 or 6 per round if they get an extra bleeding result as a permanent wound.
In addition to bleeding faster, there's one obvious danger: a character who is still in the fight has a greater risk of being targeted by opponents. It's one thing to be lying on the ground bleeding, but another thing to be bleeding out while also under attack. I like this rule a lot; it gives players in a desperate situation an extra chance to help their comrades, but at greater risk to their own mortality, and it leaves that choice in the hands of the player.