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Balancing slow moving projectiles

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X3M's picture
Joined: 10/28/2013

I guess, I have to make this easy (for myself). And start from scratch. Henceforth the deletion of the entire first post.

For my game:
I have these fast moving and slow moving projectiles.
Attackers might fire from close by or far away.
Targets might move around too, during the battle. Only then, this mechanic comes in action.

Attackers too, can move around while they fire. But this of course brings extra problems for the attacker. But it might be a strategic choice like a retreat or such.

But here is the thing. I kinda have trouble getting the mechanics around this "want it all", right. It is constantly half-assed crap that doesn't cope with reality somewhere.

That the mechanics don't work was an accidental discovery. This due to the fact that I wanted slow moving projectiles as well (cheap artillery and stuff)

There are only 3 statistics to work with, divided into 4:
R -Range of the attacker.
St -Speed of the target.
Sa -Speed of the attacker.
H+/H- -Adjustments to the speed of the projectile (faster or slower, H stands for Homing).

From this, I like to derive a penalty number. This number is going to be 0=good, to 6 or higher=a complete miss. The numbers in between are going to be an extra accuracy roll.


How would you deal with this? How would you determine the penalty number?

X3M's picture
Joined: 10/28/2013
Changed the above post into a

Changed the above post into a different approach. I hope I can get an solution. Because having a natural RPS effect on structures is an absolute wish of mine.

bartergames's picture
Joined: 10/22/2016
One approach

If I've correctly undestood, you need to calculate a penalty (lets say) 'p' as a function of 'R', 'St, 'Sa' and 'H':

p = f(R, St, Sa, H)

One way is decompose that in:

p = 6 * ( f1(R) + f2(St) + f3(Sa) + f4(H) )/4,

with each single function ranging from 0 to 1 (So 'p' will range from 0 to 6).

Each function models how the stat affects the "penalty". As an example, for 'St' you can argue that the more the speed of the target the high the probability to miss the shot, so it could be:

f2(St) = St / max(St)

It's up to you how do you want to model those functions ;)

A more general template would be:

p = 6 * ( a1 * f1(R) + a2 * f2(St) + a3 * f3(Sa) + a4 * f4(H) ),

with each single function ranging from 0 to 1 and

a1 + a2 + a3 + a4 = 1

this way you can balance the relative importance of the stats (R, St, Sa, H) in the final value of p.

The hard part, I guess, is how to simplify the calculations to accomodate for a board game. Maybe calculating all the possibilities and write them down to a "lookup" table in the rules? :|

Joined: 10/27/2016
If you want to make it easy

I would add to the previous poster and simply assign a relative rating to each range of the variables.

Each variable would have a 0 for easy, 1 for normal, 2 for hard...if anything presents beyond what you think would be hard, the shot is nearly impossible and you can only make it with whatever your analog to a "crit" would be (i.e. a 20 on d20). If you need more granularity with those corner cases you can make it 2 crits in a row for something crazy (which on d20 is a 1/400 chance).

As an example I would set up:

Range 0-30 yards= 0, 30-60 yards =1, 60-90 yds =2
Speed of target 0-10 mph = 0, 10-20 = 1 20-30 = 2
Same for speed of attacker
Speed of missile (assuming crude weapons) 100+ mph = 0, 75-100 mph = 1, 50-75 = 2

Add em up. The most difficult normal shot has -8 penalty.

Of course scale the numbers and units of measurement to make sense for your game.


X3M's picture
Joined: 10/28/2013
Simplicity is key for a

Simplicity is key for a streamlined board game. So simply adding and substracting should be allowed. With this in mind, I attempted as such myself without success.

This is what I did:


The board is a hexagon grid.
The ranges of the variables that I am talking about are:
Range is 0 to 9
Speed is 0 to 9
For the homing ability, I have yet to figure out what numbers would be best.

For simplicity, each penalty that is below 0, will remain 0. And each penalty that is above 6, will be 6.

For now, I was thinking about 1d6 for the penalty roll.
Rolling the #Penalty or less is a miss.

Of course, no penalties, means no rolling.
And a penalty of 6 means a miss any way, thus no rolling needed since it is automatically a miss.


A basic situation in the game:
Attacker has a range of 5.
Target stands still. Thus there are no penalties.

Target is slow:
Now, if the target decides to move, and has a Speed of 3.
The speed is compared to the range. 3 and 5. The lowest number indicates how much of a penalty will take place.
In this case, the 3. The attacker will miss if (s)he rolls a 3 or less.

Attacker has short range:
If for example, the attacker has a range of 2 and the target moves with a speed of 4. Again, the speed is compared to the range. In this case, 2 is the penalty.

If the attacker and target both move:
If the attacker has a range of 3 and moves with the speed of 3. And the target moves with a speed of 3. The penalty will be 3 for the attacker by its own movement. And a second penalty will be 3 by the movement of the target.

With the above, structures which have speed 0. Will not provide penalties.
The same goes for melee weapons.


The problem starts when I introduce the Homing missiles and slow moving projectiles.

Structures should still provide 0 penalty.
Melee should also still provide 0 penalty.

Fast units should provide LESS penalty when there is a homing ability.
Fast units should provide MORE penalty when there is a slow moving projectile.

But how to implement this in the mechanic as simple as possible. Without having the players calculate?

bartergames's picture
Joined: 10/22/2016
The 1D6

You could implement "homing" and "slow projectile" as "modificators" for the 1D6 roll, something like:

"homing" present: 1D6 + 1 (adding to the 1D6 increases the likelihood of a hit)

"slow projectile": 1D6 - 1 (substracting from the 1D6 increases the likelihood of a miss)

Experimental Designs
Experimental Designs's picture
Joined: 04/20/2013
I have a similar dilemma with

I have a similar dilemma with my spaceship game with the exception it isn't the projectile itself, but the types of weapons being used.

Speed and distance are huge modifiers to the overall effectiveness of ship to ship weapons. All weapons have unlimited range because it's in space and nothing there to alter it in any way such as friction, air speed, wind resistance, gravity and etc. like in an atmospheric environment.

You may want to refer to what they did in Battletech where they took the rating of the pilot's gunnery (in this case lower is better) plus the amount of movement done and however much the target has moved. You add these up and you need to roll equal to or greater in order to hit. Some weapons have gunnery penalties to represent the cumbersome nature of weapons such as ordinance and artillery.

X3M's picture
Joined: 10/28/2013
I have been pondering a lot on this one

tldr ahead

Experimental Designs wrote:

You may want to refer to what they did in Battletech where they took the rating of the pilot's gunnery (in this case lower is better) plus the amount of movement done and however much the target has moved. You add these up and you need to roll equal to or greater in order to hit. Some weapons have gunnery penalties to represent the cumbersome nature of weapons such as ordinance and artillery.

In my case as well, lower is better. Somehow, I like this much more than the higher is better.

Cumbersome weapons, yes. I would like to have them. The artillery is going to be one of them. I already spend a lot of time on the "instant" shooting artillery. To get it balanced.

This Homing/Slow effect is simply another addition. Which is not only going to be used on some artillery. But also on other weapons like "instant" lasers and "slow aiming" cannons.

I seek a mechanic, that can't be abused. As for now, the subtracting/adding rule doesn't work well. Even with Bartergames suggestion (which did help). It doesn't feel right in certain cases.

Further notice: This rule is only applied if the enemy decides to move. Or if the attacker did a move + attack.

So, my next step is to try something with a multiplication. Multiplications will not adjust 0. It has to remain simple too, which is harder with multiplications. Thus numbers like 2 and 3 are going to be used.
I seek balance later, first the mechanic has to work properly.


Now then, having the multiplication of 2 would mean that an unit that is standing at a range of 4. Will act as if it has range 8 in case of a slow projectile. And a range of 2 with a fast projectile. Instant projectiles will be having "0".

An adjustment to range will also mean that the order of firing will change. Which is logical. But doesn't combine well. The unit has a range, and a distance in this.

The speed of the target will also be treated the same way. Depending on the weapon. A speed of 2, will be only 1 in case of the fast. 0 in case of instant hits. And 4 in case of the slow projectile.

With this:
Melee will remain at 0 penalties.
And targeting structures will also provide 0 penalties. (Although, a "higher" range, means that this shot is dealt later on)


Problems with this is that the rules are not clear yet. I have to decide which range to use.

-Range of the unit
-Distance on the board

The same goes for the speed.

-Speed of the unit
-Travelling distance on the board

And then there is this, having to round, problem. It only really matters for the speed that is used.

So, perhaps I should leave the speed multiplication/dividing. Out of the concept.

It doesn't matter for instant hit weapons. But it does matter for the slow projectiles. It pains me, that this might become 2 separate rules. 1 for fast projectiles and 1 for slow projectiles.

I'll keep on pondering.

Experimental Designs
Experimental Designs's picture
Joined: 04/20/2013
I think sticking to simple

I think sticking to simple maths instead of multiplication is the best way to go about this unless it is something simplistic such as range bands and not through the entirety of the game itself.

There is a way to have a universal rule for both fast and slow projectiles, it is a matter of making a scale or a chart that fits if you want that level of detail.

X3M's picture
Joined: 10/28/2013
How did you handle this?

In the mean time, how did you handle this? Or are you also still pondering?


The rest is TLDR. But I post it any way to show the little progress that I have made.

Turns out that the calculations are to detailed.
The situation can be splitted.
And it is either scrapping the idea, or making the most of it by using only the maximum possibilities.


Busy life refrains me from doing something about this problem in a detailed calculating sense. However, I did some doodling in my head for the logic and balance. And the way of how to implement this "story" based into the game.

Turns out, I have 2 different ways of approaching this.

Homing missiles and Instant hit weapons can act differently in the game.

Instant hit weapons (lasers/rail guns) act as if they have 0 range for penalty. But also for the order in shooting. They go first.

Homing missiles. Every one can picture these, hitting any way. However, they too need time to reach the target. Thus they have their order of shooting determined by their range. Yet there will be no penalty on the hit chance.

I need to simplify this to a yes/no situation. Using "in between" numbers seems to be a no go for now. Since it makes no sense to have a partly homing missile and a partly instant hit weapon.

The multiplication however seems to be the best way for the slow projectiles. And multiplying with infinite (a big Yes to adjustment) would mean, dividing by the maximum balancing factor. This would mean, this weapon goes last in the order of firing. And it would also miss 100% when the opponent chooses movement.

If I am to use homing weapons that only have a small effect. Than these will have their factors not based on their "other" range. But a new accuracy factor.
Maybe I re-use the basic accuracy, and tell players to roll it twice for certain units.

Now, I am not sure if the homing missiles are the twin partner of the "slow". Or the instant hit weapons are the partner of the "slow". Maybe both, or maybe there will be 2 kind of slow weapons. Probably the second. Since I like the idea of fast aiming, slow hit and slow aiming with fast hit.

Any way, that would make things more complicated again. So, I keep on pondering for now. This addition to the game is not needed yet. Since I am still play testing the previous addition (artillery).


First reference balancing:

No adjustments remains weighing 1
Adjustment "effect" weighs 2
Average adjustment (by choice) weighs 1.5

Thus a maximum effect is +50% on a weapon.
Or a +25% on the costs of a basic unit.

Al in between will be less than these factors.

Joined: 08/21/2015
Hi there I've been following

Hi there

I've been following this when work allowed (ie. not as often as I'd like),
so I have a few (possibly irrelevant and definitely late) thoughts.

First, I think you need to take into account the speed difference (or ratio) of the projectile and the target in order to determine whether the projectile is "slow" or not. So for a subsonic Harrier jet, a Mach-2.5 sidewinder missile is fast, while for a Mach-3+ SR-71 it is definitely slow. An RPG is relatively fast against a tank, but slow against most aircraft. WWII naval torpedos are also a good example of slow projectiles; the fastest of them were only slightly faster than the fastest destroyers or torpedo-boats, and less than twice the speed of virtually all battleships.

Also, homing weapons might well be slower than equivalent non-homing; manoeurvering takes time, and difficult to do effectively at high speeds for various reasons. And if you (as a projectile) are fast enough, you don't need to adjust your flight path (eg. rail-gun slugs)

X3M wrote:
Instant hit weapons (lasers/rail guns) act as if they have 0 range for penalty. But also for the order in shooting. They go first.

Homing missiles. Every one can picture these, hitting any way. However, they too need time to reach the target. Thus they have their order of shooting determined by their range. Yet there will be no penalty on the hit chance.

Both of these sound good - but following my suggestion that homing weapons are slower, I might take them into account after dumb weapons (or better, dumb weapons of a similar class, if that doesn't introduce too much complexity).

X3M's picture
Joined: 10/28/2013
Gilamonster. You got a good

Gilamonster. You got a good point there. Perhaps, the initial penalty needs to be changed entirely. Before I even start touching the different weapons.

When I didn't even tought about these type of weapons. I had a simple penalty rule to encourage players to use the movement more often. In case of an attack. Also, certain melee units where relatively obsolete. And with the penalty rule, they where of use, by choice.


The Original penalty rule:
Range of the attacker is compared with the Speed of the target. The lowest number counts for # penalties. Each penalty was a die roll of 5/6th. (Thus 1/6th chance of a miss).
The same went on for if the attacker self was also moving. Thus its own speed was compared to its own range.


This meant that melee units where very good at assault (attack+move)
And long ranged units had easier time, dealing with the slow units or structures. They simply couldn't run properly.

Of course, these roles suddenly became the primary choices. And the new weapons are simply a secondary layer to the strategy.

Now, I am not saying that the penalty rule was originally good. It was a bit overpowered when both players had plenty of action points. But it served its purpose. And the action point cost to activate this was high enough to have a normal game balanced.

X3M's picture
Joined: 10/28/2013
After studying Warzone2100.

After studying Warzone2100. And some brainstorming about all the wonder aspects of this game. I have thought of how it actually might work.

The original rule had one flaw, and that was that I compared speed with range. Thanks to Gilamonster, I started to see this.
They should not be compared. But multiplied with each other instead.
How did I come to this conclusion?

Well, a moving object is harder to hit, when it moves faster and faster.
Shooting from a distance is also harder and harder.
However, an object that doesn't move, can get hit directly from any range.
Each unit tries to hit. So obviously they aim there where the enemy might end up. A longer distance or a faster target, both means a more difficult aim.

Please keep in mind. I am using the distance on the board for the shooting and the movement, not the statistics of the units.
Thus adding up R and S isn't logical.
R x S = logical.

A -Now, having instant weapons means, multiplying the answer with 0.
B -For fast projectiles, I can divide the score by a given number.
C -Slow projectiles can provide a multiplying factor.
D -And projectiles that are "too slow" will have a factor of infinite.
E -Homing missiles will have the Range and/or Speed reduced by subtracting instead of a division or multiplication.

I will end up with a table of reference if I where to do this all. So I think that I need to tum tie do apply quantum game mechanics this stuff time.


Taking the above in account. I guess that I have to divide the multiplication of R and S. Into either 2 or X die rolls. So that players don't have to do much math.

So I got 2 options here:

Option 1:
With 2 die rolls, I roll 1 die for the Range. It would be (6-R)/6th. This means that a Range of 6 and above is always 0. Personally, I don't like it.
I do the same for the Speed for any die that remains as a hit.
Again, 6 Speed or more means always a 0. And I don't like it.
But maybe, I need to take my time to accept it.
I only want to use D6 if you guys don't mind.

Option 2:
I take the lowest of the 2 again. Thus either R or S.
I use this value for (6-RorS/6th).
But now I roll this die X times for the other value.
This means that if 1 of the 2 value's is 5 or less, there will always be a chance.
It can grow exponentially low though. And a play test might show that this is.... stupid? smart? I don't know.

With these 2 options, I can implement them all 5. They all will be an adjustment on R. And this will be simple math.

A - You never have to roll. It's a hit.
B - R / Adj.
C - R x Adj.
D - You never have to roll. It's a miss.
E - Either R - Adj. or S - Adj. or Both - Adj.

E could be combined with B and C. But in that case, I don't know yet If I apply E first, or B/C first. It is a big difference.
If it doesn't work while the rest does. I will scrap this idea of combining E with B/C.


B is still troublesome to do. It gives fractures. Although, rounding upwards now seems not much of a problem to me.
But C can be a die roll as well. However, I would be stuck with 5 options on that one.

Let me know, what you guys think. I bet there is a lot of room for improvements. And I am not sure about the open choices that are left for me.

X3M's picture
Joined: 10/28/2013
Playtested each, 2 times

Option 1 seems to be the better of the 2.
Main reason; only 2 die rolls.

I play tested both options with values 6 and less.
Then I play tested both options with values 12 and less.

While option 1 is the better one. It yields 75% miss as a minimum for the whole game.

The 2 rolls:

My wish is to only use D6.
No other dice. No other method's like cards or so.

Perhaps re-rolling the dice that missed?

Has anyone an idea, how to increase the chances of a roll to be an hit?

My friend joked about rolling a yes/no for if the rule is being applied. But that might work too.

X3M's picture
Joined: 10/28/2013
Fail after fail

I went further with option 1. It doesn't work. :(
ONE big "bug" abuse in this.

Option 2 does not have the bug. But doesn't work for other reasons.

Back to the drawing board. :(
I just feel that there is something with S x R. And that I have to find a way to work with that!

X3M's picture
Joined: 10/28/2013
My next attempt.

This is one of those posts, that has been rewritten several times before posting. But at least it brings order to my thoughts. :)

I went back to comparing S with R and let the players choose the lowest value. (It is still the best and easiest mechanic so far)

A die roll is 5/6th for keeping it a hit.

Since dividing by a number doesn't work. It is either.
Instant; 0 x the value
Normal; 1 x the value
Slow; 2 x the value

If it is 2 x the value, players need to roll twice as much.

I am not going to use other value's, due to balancing issue's. And I am not sure yet about the numbers that I am using.

Anyway, all melee weapons and structures will yield 0 rolls.

The effects on the weapons are only at a distance. Thus the balancing factor is only on R. I am currently using:
+0,4 x R for Instant (Fast + Homing)
+0,3 x R for Fast
+0,3 x R for Homing
+0,2 x R for Normal
+0,2 x R for Slow Homing
+0,1 x R for Slow

Homing missiles add +0,1 x R.

Effects in the game:

- Instant
Will go first.
Will yield 0 rolls in case of dodging.

- Fast
Will go first.
Will yield # rolls in case of dodging, since well, the unit simply doesn't aim well.

- Homing
Will yield 0 rolls in case of dodging.

- Normal
Will yield # rolls in case of dodging.

- Slow Homing
Will go later, the Range x 2.
Will yield 0 rolls in case of dodging.

- Slow
Will go later, the Range x 2.
Will yield 2 x # rolls in case of dodging.


Play testing is needed though.
The list doesn't seem to be completely logical.
But let me hear your thoughts as well.

If it works, I will start a topic for better names.

Joined: 08/21/2015
Ok, I have a few minutes to

Ok, I have a few minutes to post again - yay!

I actually like your most recent proposed rule - I think it might be logical enough and practical enough (even if you as designer would prefer a more logical or elegant solution). But play-testing will mean more than my opinion.

Going back a bit if I may, did your previous discarded "option 1" fail because of the "R or S > 6 -> automatic miss" issue? If so, I have a simple suggestion (but perhaps one you've already tried and rejected) - instead of rolling 1D6 for each of R and S, roll 2D6 each. Now you've got a probability distribution between 2 and 12, and you have a resolution of more than 1 to map them to the range and speed (1-9) so you have a bit more control over the probability. Of course, it means you'll probably need a table of some sort to help players with the mapping, but I think it could be simple enough that it won't be a big nuisance (that is, they'll memorise it after a few plays). Alternatively, you could make a rule that if you roll four or more on the first die, it counts as three and you roll a second one which counts its face value, otherwise you use the value (1-3) on the first die alone. Or something along those lines, though this makes the probability calculation slightly more "interesting". Of course if that wasn't the flaw, then all this is irrelevant.

PS. I'm glad I'm not the only one still playing WZ2100 - great game!

X3M's picture
Joined: 10/28/2013
You might laugh at it. I made

You might laugh at it.
I made the same error again in that one:

If Range means an automatic miss. Why should I roll if the unit can't move?
Now you might say that, hey, if they don't move, the rule doesn't work.
But the very next one is a movement of 1.
It's slow. I don't see an automatic miss happening on slow.
The same was for melee units. If an enemy units moves at any speed. Melee should roll 0 times. Thus always a hit. By option 1. This was not happening.


I thought about your suggestion.
The thing is, some battle's have like 20 dice.
Having to roll 20 times a pair of dice takes to long.
And I don't know a way to roll them fairly by using 2 colours or such.... but then again. I didn't calculate on that yet.
I will take a look into it as well. Just to be on the safe side.


I still need to work on my latest attempt. I did some explanation to a co-worker. But during that, I discovered a flaw. I need to simplify more.

I saw 3 factors, blending together, but also being separate in other combinations. The curve is wobbly. But that is math talk. I need to reduce it into 2 factors by some simple rules. Perhaps, even just 1.

Something along the lines of:
A story that tells the player what the weapon does.


In Warzone2100, my name was X3M.
Perhaps, we played together :)

I was that bastard that went 6-12 Cobra Hoover Missile Battery rush on an fairly open map. Harrassing players bases and running away from their armies. :)

Which is.... something that I like to add to my game :D.

X3M's picture
Joined: 10/28/2013

I playtested this stuff. I got good and bad results back. The story seems to be going into 2 directions.

I had to discard the homing ability. The curve depends on the value adjustment. Thus a story on the unit card, plus a value is what I have to use. If it has a homing ability, than this is intergrated in the value adjustment.

Projectile speed is not going to alter the subturns. For this, I need a new adjustment factor. I am still searching for it. All I know is that using it together with the value adjustment, means an imbalance.

Value x2 is no longer the down limit. I discovered that value x infinite is the true down limit. I was able to make a new list. And funny enough, players do feel the difference between value x2 and value x3. In play style, but also in the subtle balance factors.

The list is now:
Value x0 will be 150%. Or 0,3R
Value x1 will be 100%. Or 0,2R
Value x2 will be 75%. Or 0,15R
Value x3 will be 66,7% Or 0,133R
Value x4 will be 62,5% Or 0,125R
Value x5 will be 60% Or 0,12R
Value x infinite will be 50%. Or 0,1R


Questions for me that remain.

The above is for the maximum ranges of the units. I still have to test all the other ranges from maximum to 0. And see if the intended factors are indeed worthy to use.

What do I have to do, for balancing the subturn?
That is, if I truly want lasers to fire first as well. Not just hitting moving targets. This factor is going to be different than the projectile speed. I guess, I call it the aim speed.
But it is this factor that will show the thematic difference between homing missiles and lasers.

X3M's picture
Joined: 10/28/2013
After checking the first

After checking the first question. I had another debate on balance, since it did not feel well.

We (not just me) decided on going with 200%/100% with each step.
This means that the value multipliers of 0, 1 and 2 will remain the same. Infinite as well. But 3 and higher will have different balance factors once again.
With this, only 3 can show some interesting differences. And 4 in a very rare case.
But all other value multipliers are from now on ridiculous.

Keeping my fingers crossed for the next test.


And by the looks of it. I have to do something similar for the altered sub turn balance.

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