In Need of a Simple Dice-Combat System

Hey Sly,

First off -- GREAT idea, over all!

I've been tinkering with a card-base RPG system for a bit, too, and I'd love to see how you've tackled certain problems -- but that's for another post.

For *this* reply, let me make sure I understand what you're asking:

1) You're looking for ideas on how to differentiate weapons when using a single 6-sided "to hit" die.

2) You're looking for commentary about systems like SDE and Death Angel, which use non-standard sides on the "normal" 6-sided die.

3) You're looking for commentary about the proposed damage system, with greater and lesser dice.

Before diving into those three subjects, I have to ask: what are your design goals for this system?

Speed?
Simplicity?
Realism?
Other?

Based on your description of the game, I would say speed and simplicity are your two highest priorities, but that's a guess. If I'm wrong, everything I say will be crap. Even if I'm right, it might be crap, so feel free to disregard. :)

I'm going to start a new post for the individual answers so this doesn't turn into a wall of text.

1) How does one differentiate weapons in a combat system that uses a single 6-sided die?

Your biggest asset are the cards in your RPG. Some of your big challenges are: only 6 results per die, a flat probability distribution (if you're only using 1 die to compute results).

Some ideas that come to mind:

1) Encode a "to-hit" chart on each weapon's card, with different different cards having different charts

2) Allow combatants to play their weapon cards either offensively or defensively each turn, adjusting combat results appropriately.

3) Combine 1 & 2, putting a "defensive" and "offensive" table on each weapon card, which can then be played right-side-up or upside-down to determine which chart is used each turn.

4) Consider changing the role of defense. Back when I played D&D, it used a cross-reference between attacker level and player armor class to determine the chance of success. If you adopt that system, you'll probably have to use tables. Alternatively, you could use a system like HERO, which turns armor into a straight subtraction from the damage role. This removes it from the "to-hit" role, simplifying things.

5) Consider using more dice. D&D uses a single "to-hit" die, but by using tables it generates a wide variety of mathematical success curves. If you use more dice, the probabilities already follow a nice bell curve, and you can get rid of the tables while still having an interesting feel to the game.

For example, you could use a symbol system like SDE or Memoir '44. The faces on the die could be skulls, drops of blood, shields, blanks, whatever. Then, you could put different symbol combinations on each weapon card, signifying different results. For example, 2 drops of blood on the dagger card might be "1 pt of damage," whereas the same result on the long sword might be "3 points of damage," because it's a more "powerful" weapon (and probably costs more).

Results need not be shared by all weapons. For example, the dagger might have a "skull + blood + shield" result that signifies a "back-stab" that does 2 points of damage and ignores armor, while the long sword doesn't have that combination at all.

I use a variation of this in my card-based RPG combat system. I use color dice, where "white" is a "wild" result you can flip to any color, red = damage, blue = defense, green = movement, yellow = special, and black "kills" the die, removing it from re-rolls. On a player's turn, he divides up his dice into attack and defense piles. He rolls his attack dice and subtracts off any black results. Blue results he sets aside for his defense plays. All others he uses to build color combinations that match "abilities" on his cards. For example (it's a superhero game), a character with Energy Blast would have the following card:

Energy Blast
1+ red: damage = red pips
1+ green + 1 yellow = "force blast" = pushes enemy back spaces equal to green pips
etc.

There are 4-6 results per card.

As the player is attacked, he rolls his defensive dice and totals blue pips, using those to activate various defensive abilities on his cards. He might even have defensive abilities on his Energy Blast cards, like:

1+ blue & 1 yellow = "timed blast" = subtract blue pips from incoming damage

Black dice are always removed until the start of the next turn, so the more you roll, the greater the chance that your dice pool will become smaller.

It's a simple model that's easy to understand and has worked well, so far. Calculations are all single digit, color-counting operations anyone can do.

Thanks for the extra info, Sly -- that definitely helps.

Players vs deck with an emphasis on speed and simplicity means you could abstract out a bunch. Do you need both "to hit" and "damage" in such a system? If not, you've eliminated 50% of the rolls right there.

If building bas*** characters and smashing face are the goals, you don't have to worry about accuracy of the simulation, either. This frees you up to make some epic powers.

As an example, go back to the "color dice" example, above. Suppose that each player drafts a hand of cards to represent his character. Each card has a few abilities with various "mana" requirements. The colors on the dice represent different flavors of mana. Each turn, players divide their dice into "offense" and "defense," then roll their offense dice to try to activate powers from their hand. Think of it as "Magic: The Gathering" with each player holding a portion of the deck and land cards replaced with color dice roles. Goodness knows some Magic cards can do obscenely powerful things if the mana cost is high enough. You could do the same thing. If weapons are represented by cards, you could make each weapon feel unique by varying the mana costs and available abilities.

TLDR: D20 systems are great for what they're trying to model, but you have different requirements. Don't hesitate to abandon the model in favor of different mechanics whose math favors your design goals. I think your instinct to examine SDE is a good one.

Have you started a journal for this game?

That's a solid system. Like you say, it's fast and visual.

One danger is its lack of scalability. Your earlier post implies you want players to level significantly over the course of a session. How much do you see their damage numbers changing over the course of those levels? Said another way, if at level 1 I'm battling kobolds that do 1-3 hp per attack, what am I battling at level 15? How much damage do lvl 15 creatures do? 5-10 hp/attack? 20-30 hp/attack? In order to feel like I'm progressing significantly, the damage has to increase dramatically, and that means the number of dice increases equally dramatically.

Decoupling the symbols from literal numbers can fix this (there are other ways, too). For example, instead of 3 hit symbols equaling 3 points of damage, 3 hit icons references a particular power on the monster's card, which states how much damage. For example, a 3-hit-symbol attack by a lvl 1 kobold does 3 points of damage. The same 3-hit-symbol attack by a lvl 15 dragon does 50 points.

You might also want to consider trading in one of those blue hit symbols for a "special" symbol, like the star in Memoir '44. When players roll stars, they have the option to activate special abilities. For example, Drow Elves might be able to life leech hit points from their enemies when they roll stars. Another example: players with the "spear" weapon might be able to damage flying targets when they roll a star.

The "special" symbol lets you add variety without adding complexity.

All that said, the base system you're suggesting is solid, and will serve as a great foundation from which to tackle any curveballs you find during playtesting.

Take a look at arkham horror's combat system (rules are online). It's a pretty small system that has a lot of variables into the roll that allows to resolve encounters pretty fast.

1 - Roll only damage. Reduce by armour armour value. Each weapon is a different dice.

2.- Have mosnters that are not "bosses" be minions (1hp) with tough tactics.

3.- Roll vs defense, then apply standard damage per weapon. ANd have baddies with low HP but good tough tactics.

Normally this works for me if i wanna speed up combat.