Combat overhaul parent post

I'm rewriting the combat procedures from D&D-like games for my fantasy heartbreaker Coup Étrange. Why? I lay out some motivations here.

I got a lot of my inspiration from discussions with Eero Tuovinen and the fine folks at the Finnish RPG Theory discord server. I'm playtesting these rules with the fine folks at the Old School Table-Time discord server. Thanks to everybody involved!

The overall structure of combat is different in the overhaul. In normal D&D, you roll initiative to see who goes first, then one side goes, and then the other. Rinse and repeat. (Maybe if you're fancy you get alternating phases -- this would be my preference -- or you get to interrupt your opponent's slow actions with your fast actions, as occasionally happens in AD&D 1e.)

In my overhaul, melee ebbs and flows, as in a real fight. When you advance into melee, you commit yourself to being tied up in it for a variable amount of time, possibly unable to retreat. The alternating structure of melee rounds and maneuvers within maneuver phases was taken directly from Eero's work on Coup de Main, though I have added a few details on timing.

Everybody strikes simultaneously within a melee phase. We still roll for initiative, but it determines the flow of combat, who is in control of the maneuver, who has held their formation, rather than who goes first.

Some maneuvers are much slower (and therefore less effective) in the overhaul than in normal D&D, namely spellcasting and shooting. Just a heads up.

Read about structure, initiative, and timing here.

The attack algorithm is different too. We don't roll 1d20 + AB > AC individually anymore. Instead the whole group rolls a pool of dice together, and compares their total number of hits to the total number of hits by the enemy. The side with more hits wins the exchange and deals full damage, while the losing side deals a little spite damage.

Hits are calculated differently. We set the target number for each die based on the opponent's combat ability, armor, size, and maneuverability. (If that sounds intimidating, don't worry, it's not, it's a simple sum. Oh, and all this is compatible with your average OSR module; you can convert on the fly.) Instead of getting bonuses to hit, we give bonus Attack Dice (AD). Funnily enough, we're back to Chainmail!

I'm still working on the particulars, and parts are bound to change. For instance, I'm not positive how I'm going to handle enchanted armor here.

Read about the new attack algorithm here.

Finally, once you hit, you do some amount of damage. Well, how much?

I give benchmarks for damage numbers based on real-world injury rates, and I make a simple mechanism for modelling injuries with both formal and organic/diegetic characteristics.

The results are easy and intuitive. You won't ever have to look up the amount of damage a titanothere does again.

Read about damage scaling and injuries here.

Does it sound cool? Then you probably want to know how to convert your characters and monsters! Luckily it's quick and easy; it takes me literally 3 seconds on average.

Read about converting characters and monsters here.

The combat overhaul is now feature-complete and just needs more testing. I also need to present it in a more easily-digestible form, and explain more of the particulars in detail. I have at least one more post in the works, on calculating the target number for attack dice, especially focusing on penetration.

In the meantime, enjoy, and let me know what you think!