Elements of Good, Speedy Combat: Rolls vs. Calculations

[Mr. Mask]

What bogs down combat more? Rolling twice, or having to do math before rolling once? Generally, what are your experiences with math and constant rolling, as to which is more hindering?

The complexity of the calculations will make quite a difference, of course.

[Edge of Dreams]

If you actually roll two dice at the same time and take the higher, that's very fast. If you have to roll one die, then decide if you need to re-roll or not, that can be slow, especially if re-rolling is a limited-use ability (e.g. I rolled a 12, do I hit? No? Ok, I reroll, do my math.... does a 15 hit?).

Rolling a die and adding a number is usually pretty quick if you already have the number figured out (e.g. my attack bonus is +7, so I roll 1d20+7). It gets harder though if the number keeps changing (e.g. this round my attack bonus is 3 higher because you buffed me, but next round I need to subtract 2 because my rage wears off).

So, yeah, I'd say the thing that bogs combat down the most is when the math *changes* too often.

I don't play d20 systems as often as I used to, and one of my favorite alternate ways of rolling now is d100 roll-under (as found in Runequest, BRP, and others) - all skills, including combat skills are defined as a percentage (e.g. I have 35% in Sing, but 75% in Swordfighting). All you do is roll a d100 and try to roll lower than your skill %, no math required. Easier/harder challenges are handled by modifying your skill %, not your die roll, so a series of rolls against the same type of challenge are against a consistent target number.

[Slipperychicken]

Depends on how much math, whether you need to do it before every roll.


In my experience, what bogs down play the most is new players who need to not only recalculate their attack bonuses, but also be reminded what goes into the attack bonus, and that they need to add this number to the number on the die... and do this every round because they can't just write the total number down. Heaven help them if they're a Barbarian and their Strength score ever changes.

That's in 3.X, where you're just adding a few numbers together then adding a die roll to the result. A 3rd grade math problem (5+4+2+18 =____) to which you already have the answer will often turn into a 10 minute arithmetic lesson.

[TheStranger]

I would agree that it's not so much the math as keeping track of the modifiers, but a single die roll with a lot of modifiers tends to be what bogs things down. The wizard can add up his fireball damage faster than the barbarian can add up his modifiers from rage, bard song, flanking, greater magic weapon, power attack, etc.

That said, an experienced player can often do most or all of that math before his turn in the initiative comes up. So no matter how many modifiers the barbarian has, he can add them all up while the rogue is taking his turn so that when he comes up, he just knows that he has a +34 to hit. If the rogue changes his math by moving into flanking position, he can add that easily if he already knows the base number. Of course, if he's hit with a targeted dispel, or gets an AoO five initiative steps later and has to remember how much he power attacked for last round, it can get harder.

So to answer your original question, experienced players who are good with numbers can do either fairly quickly in most cases. But if you have players who can't keep track of modifiers on the fly, then the proliferation of modifiers is what bogs things down.

[Doug Lampert]

That's in 3.X, where you're just adding a few numbers together then adding a die roll to the result. A 3rd grade math problem (5+4+2+18 =____) to which you already have the answer will often turn into a 10 minute arithmetic lesson.

My wife, who has a masters in economics and works with numbers all the time at work, will roll a d20+15 against an AC of 19, roll an 15, and CAREFULLY STOP AND ADD THINGS UP. (This is more notable when she's tired, but that's mostly because adding twice is faster when she's awake.)

On a double attack (ranger twin-strike from fourth edition), she'll anounce one number, I'll say, "You hit", and she'll then add up the other number, even if it is plainly higher (i.e. she hit once on a roll of 10, the other die shows 15, why are you adding)?

Roll under systems this never happens, even if there are modifiers, she modifies her success chance ONCE, prior to rolling, and then does the comparison almost instantly.

We've got another player, much worse at math, and again roll under works better. In her case it also helps if there is no damage roll, and most of the time IME D&D 3.x and fourth edition you lose very little by using average damage and average crit damage rather than rolling damage and it speeds up play substantially.

Modify skill (with limited modifiers that don't change often), roll under skill, this seems to me to go vastly faster than anything else. You can even combine the damage roll or make for easy "how well do you succeed" rules by saying the HIGHER a die that succeeds is the better (roll as high as possible without going over isn't complicated, this is used in Pendragon which is BRP based and works quite well till skills pass 20).

Edited to add: My experience is that math slows things down more than you expect and is harder than you expect. Don't use division when you can use addition or subtraction, build anything complicated into a table, avoid subtraction when you can use addition. Elementary school math is still math, it will slow the game down and people who ENJOY math for its own sake probably aren't your target audience. KISS is generally good guidance, and subtraction really does take longer than addition which in turn really does take longer than a straight comparison.

[Mastikator]

Things that slow down combat, in order.

1. Confusion about rules and options
2. Indecision
3. Rolling (dice under the table)
4. The math

Explanation and possible solutions.
1. Some players are very good at learning the game rules and can easily bend them to their benefit, others struggle even after having the rules explained to them time after time, their brain are simply made of Teflon, and the worst part is that they're usually doing their best. But it's not the players job to understand the rules, it's the DMs job, my solution is that whenever a player can't or doesn't understand the rules for whatever reason then the DM simply says what the options are and the player chooses and the DM either says what to roll, or better yet, just rolls and explains the outcome. The player can learn the rules on his own time, not during a fight to the death. Making informed decisions is a privilege, not a right.
2. Sometimes players can't decide what to do, just like people take 20 minutes to decide which pizza to eat, as if it's a big deal, it's not in either case. My solution is to force the players to make a decision by putting a severe time limit (say 5-10 seconds TOPS), and if they don't decide they simply default to defensive action.
3. Rolling dice, some players have an unnatural tendency to roll the dice in such a way that it is more likely to roll under something, then the retrieving of this dice begins. A big waste of time. Obviously this happens to everyone from time to time, but some players are simply cursed with dice-under-the-soffa-itis. My solution is either A) the DM unilateral rolls for the players*, B) roll into a bowl, it'll never go away, everyone will see the result.
4. I've never seen a gaming group where there wasn't at least one person who can't quickly do arithmetics in his head, so I've decided that this problem doesn't exist. :smallwink:


*this also deals with the unfair dice problem


Constantly looking up charts is also a time-boggler, avoid crit/fumble charts at all costs.

[Mr. Mask]

I notice roll-under systems seem to be much easier for a lot of people. This is a bit surprising for me, since I seem to find roll and add systems like DnD a bit easier to calculate. Am I just unusual in this?

[Slipperychicken]

I notice roll-under systems seem to be much easier for a lot of people. This is a bit surprising for me, since I seem to find roll and add systems like DnD a bit easier to calculate. Am I just unusual in this?

Roll under means you're comparing two numbers (one on the die, one on the sheet), which are clearly visible to the player. Determining that 12 is lower than 17 is a quick, easy task. There are usually very few modifiers involved.

Roll over usually means you're determining the bonus (which can be a challenge in itself), then rolling a die, then adding the two together for a sum, then comparing that sum to the target number.


Obviously, if you've been using one method exclusively, others won't seem as intuitive.

[Mr. Mask]

Wouldn't the roll under system be worse, if you were using just as many modifiers?

[Slipperychicken]

Wouldn't the roll under system be worse, if you were using just as many modifiers?

In my experience attempting to use THAC0, yes.


Roll-over has the advantage that there's no upper bound -you can have modifiers and target numbers as high as you want. Roll-under can go into the negatives when necessary, but that can get messy.

[erikun]

Wouldn't the roll under system be worse, if you were using just as many modifiers?
This depends a lot on what system you are using.

Slipperychicken pointed out that THAC0, especially when poorly understood, tends to be confusing for a lot of people. Other people in the thread (starting with Edge of Dreams) have pointed out that roll-under percentile systems are a bit easier, probably due to being more intuitive: if a character has a 80% chance of success and the situation is giving a 15% penalty, then the player has to roll 65% or less to succeed.

One thing that hasn't been mentioned: what these systems are really doing is moving the math from the player's side to the GM's side. There are roll-under systems where you modify the player's dice roll, and they have the same problem as more typical roll-over systems. The more math you put into the GM's hands, the less likely player will be confused over it... although you may find problems with the GM getting confused. (See: THAC0)

[Mr. Mask]

But, if you had to calculate -15% from flanking, +10% from a sepll, -20% because you're raging, +5% because of another spell, and -10% from the Bard's Song--I think that's just as confusing as doing that same thing in a roll-high system?

[Rhynn]

In my experience attempting to use THAC0, yes.

But... but... that's just d20+AC+modifiers equal to or over THAC0. You can even work static modifiers (magic weapons, Strength) into your THAC0. And it's not roll-under, either!

I realize AD&D 2E especially did a horrible job of explaining it, but it's really simple.


But, if you had to calculate -15% from flanking, +10% from a sepll, -20% because you're raging, +5% because of another spell, and -10% from the Bard's Song--I think that's just as confusing as doing that same thing in a roll-high system?

A lot of modifiers will always confuse things, no matter what the system.

It does so in RuneQuest, which is d100 against a % skill (direct chance of success). It does so in D&D 3.X and Artesia: AKW, which are roll+modifier vs. target number. It does so in The Riddle of Steel, which is a dice-pool system against a target number.

Basically, it's the modifiers, not what you're rolling.

[Mr. Mask]

Makes me wonder how I can reduce modifiers without reducing tactics in combat.

[Saph]

Things that slow down combat, in order.

1. Confusion about rules and options
2. Indecision
3. Rolling (dice under the table)
4. The math

This.

Rolls vs. calculations aren't the problem. The problem is a player taking 5 minutes to quiz the DM for information, then 5 minutes deciding on what action to take, then 10 minutes arguing with the DM about whether the action is rules-legal or not. Math is fast by comparison.

[Rhynn]

Makes me wonder how I can reduce modifiers without reducing tactics in combat.

Check out The Riddle of Steel. There are modifiers, but not that much. Mostly you pay out dice from your pool for everything. It has the best tactical options out of any RPG.

[Jay R]

Two things bog down combat the most:
1. Players who don't learn the rules.
2. Players who haven't made up their minds by the time their turn comes.

The complexity of the game system makes it take longer to learn the system, but if all the players know the system, it doesn't slow down play.

Combat in a complex game of 8 decisive players who know the rules is quick.

Combat in a simple game of three players, one of whom is indecisive, and one of whom has to be reminded of each rule is achingly slow.

[NichG]

Makes me wonder how I can reduce modifiers without reducing tactics in combat.

I think the key thing is to only ever include stuff that will matter. In several of the above examples, players are doing math that doesn't need to be done because, formerly, a lower roll hit. Similarly, D&D is full of little +1s and +2s that may or may not matter on any given roll, so people have to do the math to verify that no, they didn't matter this time or yes, they did matter this time.

Example from Advanced d20 Magic:


As much as I love it, Advanced d20 Magic is vulnerable to this particular problem. In that system you must make a Fort save to successfully cast a spell, and the DCs are very high. However, you can get bonuses to your casting save from all sorts of places: Class level in applicable casting classes, feats, using a material focus (+2), sacrificing material components (+2 up to 1k, +1 for every 1k above that), spending extra time (a chart I always have to look up, since its logarithmic. 1 minute is +5), taking lethal damage from casting the spell (+5), spending XP (+1 for 100xp), naming the spell (+5), incanting the spell (+5), etc. So a caster trying to cast a DC 60 spell has to do all sorts of math to see whether or not they need to add on a little more, though they could pretabulate their casting check given maybe three or four most likely combinations of tricks.

However, lets take the above system and ask what the purpose of the casting check is. I think the designers wanted players to be able to overreach themselves and risk wild magic, catastrophic failures, etc. They also wanted casting to have some inherent risk to it. If you're willing to sacrifice the second by e.g. allowing casters to take 10 at their option, then now they only have to record for each spell what tricks they need to use in order to take 10 on it, and no math has to be done at all. Essentially the 'unimportant modifiers' have been taken out, and they only do the full counting during character updates or when they're trying to pull off something way outside of their normal safety zone.


Another thing to consider is how the modifiers are applied. Take something like D&D where there are flat modifiers you can add to a roll based on, say, higher ground, flanking, charging, poor visibility, fighting in cramped spaces, whatever. Compare it with e.g. 7th Sea or White Wolf where such modifiers change your dice pool. While in White Wolf systems you have to evaluate successes on a large number of dice at times, which can be slow, it will be much faster to apply modifiers since it just involves adding more or fewer physical objects to a handful of dice and then rolling the whole bunch.

Another thing you can do is to just eliminate stacking, so either only the highest modifier applies, or so that having any positive modifier is sufficient to get some flat bonus or benefit, and similarly for negative modifiers (though then you can get into questions of positive or negative net modifier which bring the whole thing back).

[Edge of Dreams]

Another thing you can do is to just eliminate stacking, so either only the highest modifier applies, or so that having any positive modifier is sufficient to get some flat bonus or benefit, and similarly for negative modifiers (though then you can get into questions of positive or negative net modifier which bring the whole thing back).

Runequest 6th edition does this. A skill check (roll-under %) is at one of the following levels of difficulty:


Auto-success (no roll)
Very Easy (roll against 2x your skill)
Easy (roll against 1.5x your skill)
Normal
Hard (roll against 2/3 of your skill)
Formidible (roll against 1/2 of your skill)
Herculean (roll against 10% of your skill)
Impossible (no roll, just fail)


Start with the basic difficulty of the action (combat actions are usually Normal), then take the biggest difficulty mod and just use that, no stacking. So, if you're rolling to parry an attack from behind (Formidable) while you have an arrow stuck in your arm (Hard) and you're blindfolded (Herculean), then the difficulty is just Herculean.

Yes, this system uses multiplication, which can be annoying ("Hey guys, what's two-thirds of 73%?"), but you're going to be doing this math most often on your combat skill, so the numbers can be learned pretty quickly and will be the same round to round (a Hard attack roll this round is the same as a Hard attack roll next round). Also, there's lots of times you can roll and not do the math because it's obvious (e.g. I have 66% in my skill, it's a Hard difficulty check, and I roll 62 on the d100. I almost immediately know I failed without calculating that 66 * 2/3 = 44).

[Barsoom]

What bogs down combat more? Rolling twice, or having to do math before rolling once? Generally, what are your experiences with math and constant rolling, as to which is more hindering?

The complexity of the calculations will make quite a difference, of course.
Math. Definitely math.

"I rage and charge at him"
"Okay, roll."
"Rolled a 7, with my attack bonus, that makes 14 ... does 14 hit? Wait, +2 for charge, so 16. Does 16 hit?"
"No."
"Wait, am I flanking him? Can I flank with the Crusader?"
"No, the corridor's too narrow"
"Damn. Wait, I'm raging, right? I mean, I said I'm raging before, didn't I?"
"I guess you did"
"Okay, so that hits 18."
"You hit."
"Great, so that's <rolls> 6 damage, plus 4, makes 10"
"Did you account for the rage bonuses?"
"Oh, right. 13 damage"
"Did you add the bard's song?"
"Ah, yes, 14 damage. And I guess that hit AC 19 actually."
<5 minutes later>
"Did you add damage for Leading the Charge?"

[neonchameleon]

What bogs down combat more? Rolling twice, or having to do math before rolling once? Generally, what are your experiences with math and constant rolling, as to which is more hindering?

The complexity of the calculations will make quite a difference, of course.

In order starting with the worst.

1: A combat system complex enough you have to look something up in a rulebook past your first few sessions.
2: Analysis paralysis. More than five (the low end of seven plus or minus two) meaningful options on the table at a time. (What counts as meaningful varies between players).
3: More than two modifiers to keep track of on each side of the equation. For the record subtraction and multiplication each count as two on their own and division three. Thac0 starts off with subtration. (And something visceral like adding an extra dice to a WFRP 3E dice pool counts as half).
4: Repeated rolling

[CarpeGuitarrem]

I definitely agree that you should move maths to "before the roll" whenever possible.

One of the strongest core mechanics I've seen is Burning Wheel with its dice pool system, and likewise World of Darkness. Dice Pool systems in generally, actually.

You know what you have to roll to get a success. You know how many successes you need. You assemble your pool and count how many successes you got.

If you have a penalty to the roll, or a bonus, that's reflected by taking away dice or giving dice. You don't have to do any math there, it's factored in.

Example. Let's say we're using Burning Wheel. d6s; 4, 5, 6 are successes. You have an attribute of 5, so you roll 5 dice. You get an extra die because someone's helping you. The difficulty of the roll is 3, so you know that you need to roll 3 successes. 2, 3, 3, 4, 5, 5. You barely succeed.

[Totally Guy]

Another thing that could bog down combat is the anticipated number of turns a combat will take to resolve. Requiring more combat rounds to resolve the situation makes combat longer and more of a slog.

It might sound trivial to say but I reckon it's been overlooked.

In A Wicked Age is a light game that always resolves the fight within three complete rounds at most.

[Jay R]

In 2E and 1E, I always have a table showing the "To hit" roll for each weapon on each armor class. I calculate it in Excel. So it's only a look-up.

Weapon AC10 AC9 AC8 AC7 AC6 AC5 AC4 AC3 AC2 AC1 AC0
Longswd 5 6 7 8 9 10 11 12 13 14 15
Longbow+1 2 3 4 5 6 7 8 9 10 11 12
Rapier 6 7 8 9 10 11 12 13 14 15 16
Lasso 2 3 4 5 6 7 8 9 10 11 12

[Neon Knight]

I definitely agree that you should move maths to "before the roll" whenever possible.

One of the strongest core mechanics I've seen is Burning Wheel with its dice pool system, and likewise World of Darkness. Dice Pool systems in generally, actually.

You know what you have to roll to get a success. You know how many successes you need. You assemble your pool and count how many successes you got.

If you have a penalty to the roll, or a bonus, that's reflected by taking away dice or giving dice. You don't have to do any math there, it's factored in.

Example. Let's say we're using Burning Wheel. d6s; 4, 5, 6 are successes. You have an attribute of 5, so you roll 5 dice. You get an extra die because someone's helping you. The difficulty of the roll is 3, so you know that you need to roll 3 successes. 2, 3, 3, 4, 5, 5. You barely succeed.

To provide a potential counterpoint: Dicepool systems can make risk judgement and resource expenditure more difficult. For example, I know what my odds are if I have a target of 15 on a 1d20 roll, but the odds on a 3 successes needed out of a pool of 6 dice is a little more difficult calculation to reckon off the cuff, particularly if you're not accustomed to it.

When you have to make a decision on whether to expend resources to affect such odds, it can quickly become more complicated that the simple scenario you provided.

Furthermore, you can muck up dice pools with complexity just as much as you can single roll mechanics. Shifting target success numbers up or down, having certain target numbers count double or bad numbers count negative, and so on.

Dicepool systems can have their advantages, but they can also certainly be seen as having disadvantages.

[neonchameleon]

In 2E and 1E, I always have a table showing the "To hit" roll for each weapon on each armor class. I calculate it in Excel. So it's only a look-up.


Which is one more lookup than I've used in my last dozen sessions running either 4e or Marvel Heroic Roleplaying.


To provide a potential counterpoint: Dicepool systems can make risk judgement and resource expenditure more difficult.

Depends how they are done and whether you have Fortune in the Middle or Fortune at the End. With FitM you can often expend resources after rolling. And there are several different possible dice pools. WoD uses number of successes. Classic Cortex (ack) uses the total of all dice. Cortex Plus uses your best two dice.

Roll over vs roll under: Adding is easier than subtracting. Comparing two numbers is easier than adding. If you are just rolling straight against a consistent target number (as in Marvel FASERIP) then roll under is faster. If there are any situational modifiers at all (rather than everything being classed easy/medium/hard as in FASERIP) then straight addition wins. And Thac0 introduces subtraction in counter-intuitive places.

[Knaight]

To provide a potential counterpoint: Dicepool systems can make risk judgement and resource expenditure more difficult. For example, I know what my odds are if I have a target of 15 on a 1d20 roll, but the odds on a 3 successes needed out of a pool of 6 dice is a little more difficult calculation to reckon off the cuff, particularly if you're not accustomed to it.
After a while, you can get an approximate feel for it even without knowing the exact probabilities. I find that tends to happen fast enough for it to be a non-issue.