Designing a TTRPG Combat System - Part Two

As usual, everything in this post is free to use under a CC BY 4.0 license.

This post continues where part one left off. At the end of this previous post, we had a basic combat system, and lists of different armor and weapon variations. All potential candidates - but we weren’t quite sure which to use.

But the main combat mechanic was pretty much in place:

The attacker fires a number of shots from their sci-fi weapon, targeted at the defender. How many of these shots hit, is determined by the delta of a comparative roll. The attacker rolls a d12, the defender’s die is determined by armor worn. The difference between the attacker’s weapon skill and the defender’s evasion skill is looked up on the DRT (diminishing returns table) to get the bonus, which can either be added to the attacker’s roll, or subtracted from the defender’s roll. Damage is then determined by subtracting the armor’s protection from the weapon’s damage and mulitplying by the number of successful hits.

For example: The attacker shoots a blaster rifle that fires 7 shots for 4 damage each. They have a skill of 12 in rifles. The defender wears medium armor, which gives a d8 evasion die and has protection 2. Their skill in evasion is 9.

The attacker rolls a 10. The skill difference is 3, which according to the DRT gives a bonus of 2. The total of that is 12.

The defender rolls a 7. The resulting delta is 12 - 7 = 5.

That means, that out of the 7 shots the attacker fired from their blaster rifle, 5 hit, and 2 missed the target.

The blaster rifle does 4 damage per hit - and the medium armor absorbs 2 damage per hit. That means each of the 5 hits does 2 damage, for a total of 10 damage done in this attack.

---

Diminishing Returns Table (DRT)

(a-b)	0	1	2-3	4-6	7-10	11-15	16-21	22+
Bonus	0	1	2	3	4	5	6	7

Where a is the weapon skill of the attacker, and b is the evasion skill of the defender.

---

Weapon Trials

Let’s try out a set of weapons against a set of armors, and look at the damage numbers we get.

Choice of Armor Set

Let’s start by picking one set of armors to test the weapons against:

Armor Set	light	medium	heavy
protection	1	2	3
evasion die	D10	D8	D6

I’m picking this one set specifically, because it does allow us to maybe add a superlight armor with protection 0 and maybe a super-heavy with protection 4. But also would allow us to switch light armor to d12 and heavy armor to d4 - should we need a larger difference. Apart from that, we can also reduce all protection by 1, giving us light = 0, medium = 1 and heavy = 2. This feels like a good starting point to begin with, because we have so many possibilities to tweak it later.

Choice of Weapon Set

As for weapons - last time we ran into an overwhelming amount of choice there - and suffered from decision paralysis. So, I’m taking a step back there, and restricting myself to start with only three weapons. We can always add more later - but for our baseline, just three. Why three? That number worked well for armors, so maybe it works here as well!

We’ve looked at weapons firing anywhere from 1 to 9 shots. And we’ve seen that things get difficult at the extremes. So may, let’s ignore 1 shot, 2 shots, 8 shots and 9 shots for now. The two outermost values on each side. That leaves us with weapons 3 shots to 7 shots. So, let’s just try using 3 shots, 5 shots and 7 shots as our three baseline weapons. Just 3 regular rifles, one with lower number of shots, higher damage per shot, one higher number of shots, lower damage per shot, and the average one.

As for damage, let’s try finding something that gives all three weapons a somewhat equal damage potential. We can always adjust damage later, if it doesn’t work out. Trying around with a few numbers, the following catches my eye: 3x5 = 15, 5x3 = 15 and 7x2 = 14. That’s pretty even. But, our average armor has a protection of 2 - so to counterweigh that, let’s add another 2 to each damage:

Weapon	shots	damage	vs. light	vs. medium	vs. heavy	average
Blaster rifle	7	4	21	14	7	14
Photon rifle	5	5	20	15	10	15
Pulse rifle	3	7	18	15	12	15

Looking at the Base Damage

This previous table shows the maximum potential damage - but we do know that light armor is harder to hit and thus will take less hits on average, while heavy is easier to hit and will be hit more often. So, let’s look at the actual expected health-damage, when respecting the chance to hit:

Weapon	shots	damage	vs. light	vs. medium	vs. heavy	average
Blaster rifle	7	4	6.6	5.3	3.2	5
Photon rifle	5	5	7.6	6.9	5.4	6.6
Pulse rifle	3	7	8.2	8.1	7.5	7.9
average	-	-	7.5	6.8	5.4	6.5

We get something we don’t truly want. Heavy armor is just plain better than medium which in turn is just plain better than light. Pulse rifle is just plain stronger than photon which in turn is just plain stronger than blaster. But, I already wrote in the last post, that the plan is to add energy shields to armors, as another layer of defense. And that means, heavy armor is best only when no shields are in play, and the same is true for the pulse rifle.

For now, all we need is that the numbers aren’t completely out of whack, but remain mostly sane. It’s okay that we now have a best armor and a best weapon - as long as these strengths do get counter-balanced once we add shields. That means we do need shields to work in such a way, that blaster rifles and light armor are the best choice for that.

Inventing Shields

To achieve that, we want to add shields that profit from evasion, and are weaker against weapons firing many shots. We do have some leeway here, because we have not defined yet, how many hit points or shield points a character will have. We have the ability to increase or decrease one versus the other. In general we want shields to work a bit like temporary hit points do Dungeons & Dragons. We want them to sit on top of your regular hit points, be consumed first, and replenishable. But we do not want to use the same damage model, where Pulse rifle does the most damage, and were heavy armor receives the least damage.

So, let’s just define that each hit reduces shields by 1 point, regardless of how much damage that hit does. That makes blaster (with many shots fired) stronger than pulse (wich fires few shots) - and also makes light armor (with the higher die for evasion) take less shield damage than heavy armor (which gets hit more often). How would that turn out?

Weapon	shots	vs. light	vs. medium	vs. heavy	average
Blaster rifle	7	2.2	2.7	3.2	2.7
Photon rifle	5	1.9	2.3	2.7	2.3
Pulse rifle	3	1.4	1.6	1.9	1.6
average	-	1.8	2.2	2.6	2.2

This table now shows shield-damage instead of health-damage. And indeed we got strong and weak reversed: light is now best armor, and blaster is the best rifle. We also see, that on average, shield damage is roughly one third of health damage. And that is perfectly fine - we can make shields points be roughly one third the amount of health points, if we do want them to play equal roles.

Comparing Skill Differences

We must keep in mind though, that in a normal roleplaying encounter, the players are supposed to win, and the enemies are supposed to die. So, we do expect that players normally encounter enemies that are either weaker (lower skills), or numerically inferior. So maybe, we should rather look at enemies that are a few skill points lower.

This difference in skills can result in a bonus (using the DRT) ranging from -7 (weak attacker vs. strong defender) all the way to +7. Let’s take a look at how our weapons and armors handle that:

Blaster rifle	SD-L	SD-M	SD-H	SD-avg	HD-L	HD-M	HD-H	HD-avg
Bonus -7	0.17	0.21	0.28	0.22	0.50	0.42	0.28	0.40
Bonus -6	0.29	0.36	0.49	0.38	0.88	0.73	0.49	0.70
Bonus -5	0.47	0.58	0.78	0.61	1.40	1.17	0.78	1.11
Bonus -4	0.70	0.88	1.15	0.91	2.10	1.75	1.15	1.67
Bonus -3	0.99	1.24	1.60	1.28	2.98	2.48	1.60	2.35
Bonus -2	1.34	1.67	2.10	1.70	4.03	3.33	2.10	3.15
Bonus -1	1.75	2.15	2.64	2.18	5.25	4.29	2.64	4.06
Bonus 0	2.21	2.67	3.21	2.69	6.63	5.33	3.21	5.06
Bonus +1	2.71	3.22	3.79	3.24	8.13	6.44	3.79	6.12
Bonus +2	3.23	3.78	4.36	3.79	9.70	7.56	4.36	7.21
Bonus +3	3.77	4.33	4.90	4.33	11.3	8.67	4.90	8.29
Bonus +4	4.29	4.85	5.40	4.85	12.9	9.71	5.40	9.33
Bonus +5	4.79	5.33	5.85	5.32	14.4	10.7	5.85	10.3
Bonus +6	5.25	5.76	6.22	5.74	15.8	11.5	6.22	11.2
Bonus +7	5.66	6.13	6.51	6.10	17.0	12.3	6.51	11.9
average	2.51	2.88	3.29	2.89	7.52	5.75	3.29	5.52

The Blaster rifle deals the most shield-damage and the least health-damage overall. It benefits greatly from increased bonus, making it strong against enemies with lower evasion. Therefore it’s also quite effective at taking out the shields of heavily armored enemies - while being weak against heavy armor, once shields are down.

Photon rifle	SD-L	SD-M	SD-H	SD-avg	HD-L	HD-M	HD-H	HD-avg
Bonus -7	0.17	0.21	0.28	0.22	0.67	0.63	0.56	0.62
Bonus -6	0.29	0.36	0.49	0.38	1.17	1.09	0.97	1.08
Bonus -5	0.46	0.57	0.76	0.60	1.83	1.72	1.53	1.69
Bonus -4	0.67	0.83	1.10	0.87	2.67	2.50	2.19	2.45
Bonus -3	0.92	1.15	1.47	1.18	3.67	3.44	2.94	3.35
Bonus -2	1.21	1.50	1.88	1.53	4.83	4.50	3.75	4.36
Bonus -1	1.54	1.89	2.29	2.18	6.17	5.66	4.85	5.47
Bonus 0	1.91	2.29	2.71	2.30	7.63	6.88	5.42	6.64
Bonus +1	2.30	2.71	3.13	2.71	9.20	8.13	6.25	7.86
Bonus +2	2.70	3.11	3.53	3.11	10.8	9.34	7.06	9.07
Bonus +3	3.09	3.50	3.90	3.50	12.4	10.5	7.81	10.2
Bonus +4	3.46	3.85	4.24	3.85	13.8	11.6	8.47	11.3
Bonus +5	3.79	4.17	4.51	4.16	15.2	12.5	9.03	12.2
Bonus +6	4.08	4.43	4.72	4.41	16.3	13.3	9.44	13.0
Bonus +7	4.33	4.64	4.86	4.61	17.3	13.9	9.72	13.7
average	2.06	2.35	2.66	2.36	8.24	7.04	5.31	6.87

The photon rifle is average all around, with neither particular strengths, nor weaknesses. It’s the Jack of all trades, master of none.

Pulse rifle	SD-L	SD-M	SD-H	SD-avg	HD-L	HD-M	HD-H	HD-avg
Bonus -7	0.16	0.20	0.26	0.21	0.95	0.99	1.06	1.00
Bonus -6	0.26	0.32	0.43	0.34	1.55	1.61	1.72	1.63
Bonus -5	0.38	0.48	0.64	0.50	2.30	2.40	2.56	2.42
Bonus -4	0.53	0.67	0.88	0.69	3.20	3.33	3.50	3.34
Bonus -3	0.71	0.89	1.13	0.91	4.25	4.43	4.50	4.39
Bonus -2	0.91	1.13	1.38	1.14	5.45	5.63	5.50	5.53
Bonus -1	1.13	1.38	1.63	1.38	6.80	6.88	6.50	6.73
Bonus 0	1.38	1.63	1.88	1.63	8.25	8.13	7.50	7.96
Bonus +1	1.63	1.88	2.13	1.88	9.75	9.38	8.50	9.21
Bonus +2	1.87	2.11	2.36	2.11	11.2	10.6	9.44	10.4
Bonus +3	2.09	2.33	2.57	2.33	12.6	11.7	10.3	11.5
Bonus +4	2.29	2.52	2.74	2.52	13.8	12.6	10.9	12.4
Bonus +5	2.47	2.68	2.86	2.67	14.8	13.4	11.4	13.2
Bonus +6	2.62	2.80	2.94	2.79	15.7	14.0	11.8	13.8
Bonus +7	2.74	2.90	2.99	2.87	16.5	14.5	11.9	14.3
average	1.41	1.59	1.79	1.60	8.46	7.97	7.14	7.86

The pulse rifle is generally weaker against shields than other weapons, although less so against high evasion enemies. Once shields are down, it’s generally strong though - and especially so against heavy armor. It also maintains relatively good health damage against high evasion enemies, where weapons with higher fire rates land less of their fired shots.

For closer comparsion, let’s look at the differences between pulse and blaster:

Pulse vs. Blaster	SD-L	SD-M	SD-H	SD-avg	HD-L	HD-M	HD-H	HD-avg
Bonus -7	-0.01	-0.01	-0.02	-0.01	+0.45	+0.57	+0.78	+0.60
Bonus -6	-0.03	-0.04	-0.06	-0.04	+0.67	+0.88	+1.23	+0.93
Bonus -5	-0.09	-0.10	-0.14	-0.11	+0.90	+1.23	+1.78	+1.31
Bonus -4	-0.17	-0.21	-0.27	-0.22	+1.10	+1.58	+2.35	+1.67
Bonus -3	-0.28	-0.35	-0.47	-0.37	+1.27	+1.95	+2.90	+2.04
Bonus -2	-0.43	-0.54	-0.72	-0.56	+1.42	+2.30	+3.40	+2.38
Bonus -1	-0.62	-0.77	-1.01	-0.80	+1.55	+2.59	+3.86	+2.67
Bonus 0	-0.83	-1.04	-1.33	-1.06	+1.63	+2.80	+4.29	+2.90
Bonus +1	-1.18	-1.34	-1.66	-1.36	+1.62	+2.94	+4.71	+3.09
Bonus +2	-1.36	-1.67	-2.00	-1.68	+1.50	+3.04	+5.08	+3.19
Bonus +3	-1.68	-2.00	-2.33	-2.00	+1.30	+3.03	+5.40	+3.21
Bonus +4	-2.00	-2.33	-2.66	-2.33	+0.90	+2.89	+5.50	+3.07
Bonus +5	-2.32	-2.65	-2.99	-2.65	+0.40	+2.70	+5.55	+2.90
Bonus +6	-2.63	-2.82	-3.28	-2.95	-0.10	+2.50	+5.58	+2.60
Bonus +7	-2.92	-3.23	-3.52	-3.23	-0.50	+2.20	+5.39	+2.40
average	-1.10	-1.29	-1.50	-1.29	+0.94	+2.22	+3.85	+2.34

It’s interesting to see, how the health damage difference between the two weapons peaks at different bonuses for each type of armor, and how at very high bonuses the blaster actually does more damage against light armor than the pulse rifle. This kind of variation is great - makes the weapons feel more natural, and the question “what is best” becomes a lot more nuanced and less clear-cut.

Overall this works well enough, and does naturally make weapons that are weak against armor strong against shields, and vice versa. Thus we do get weapons with strengths and weaknesses as desired, and these strengths and weaknesses do more or less balance each other out.

But right now, combat has two distinctly separate phases: first you fight against shields, then you fight against armor. And that might be fine for enemies - but players are gonna want to keep their shields up as much as they can. Armor protection only comes into player after shields are down. As a consequence, currently, evasion might be a lot more desirable to players, than armor protection.

Making The Shield To Armor Switch More Gradual

Here’s the idea: have shields reduce incoming damage (instead of completely absorbing it) - and pass the remainder through to armor.

For example, if a fully charged shield has 5 shield points, it would be able to absorb up to 5 damage in that state. A hit would still reduce it by one shield point - turning it into a 4 point shield that’s able to absorb up to 4 damage. If it recharges back to 5, it will be able to absorb 5 damage again.

If that 5 points shield is hit by a single…

• blaster shot for 4 damage - it would absorb all damage, loose one shield point;
• photon shot for 5 damage - it would absorb all damage, loose one shield point as well;
• pulse shot for 7 damage - it would absorb 5 damage, loose one shield point, and 2 damage would go through to armor

If we then assume another hit from the same weapon, against that now 4 points strong shield, then that second hit…

• for 4 damage would still be fully absorbed, reducing shields to 3;
• for 5 damage would be reduced by 4, shields would go down to 3, and 1 damage would go through to armor;
• for 7 damage would be reduced by 4, shields would go down to 3, and 3 damage would go through to armor;

This means that shields become “leaky” - because they can let some of the damage through to armor, increasingly so as they decrease in points. Armor can then soak up the remaining, lower damage - potentially keeping health damage to 0 and making it a lot more useful overall.

Now, in practice a blaster will land only 2.7 hits on average, a photon 2.3 hits and a pulse 1.6 hits. But before we properly calculate that, let’s do just a quick sanity check, assuming each weapons lands all their shots:

Blaster Rifle - 7 Hits At 4 Damage Each

1. Shields absorb 5 - 0 damage
2. Shields absorb 4 - 0 damage
3. Shields absorb 3 - armor absorbs 1 - 0 damage
4. Shields absorb 2 - armor absorbs 2 - 0 damage
5. Shields absorb 1 - armor absorbs 2 - 1 damage
6. Shields down - armor absorbs 2 - 2 damage
7. Shields down - armor absorbs 2 - 2 damage

Resulting in a total of 5 shields points and 5 health lost in the first turn. Let’s do another turn and assume the shield can recharge 2 points each turn.

1. Shields absorb 2 - armor absorbs 2 - 0 damage
2. Shields absorb 1 - armor absorbs 2 - 1 damage
3. • 1. Shields down - armor absorbs 2 - 2 damage

The second turn results in 2 shield damage, 9 health damage.

Photon Rifle - 5 Hits At 5 Damage Each

1. Shields absorb 5 - 0 damage
2. Shields absorb 4 - armor absorbs 1 - 0 damage
3. Shields absorb 3 - armor absorbs 2 - 0 damage
4. Shields absorb 2 - armor absorbs 2 - 1 damage
5. Shields absorb 1 - armor absorbs 2 - 2 damage

Resulting in a total of 5 shields points and 3 health lost.

1. Shields absorb 2 - armor absorbs 2 - 1 damage
2. Shields absorb 1 - armor absorbs 2 - 2 damage
3. • 1. Shields down - armor absorbs 2 - 3 damage

Turn 2 results in a total of 2 shield points and 12 health damage.

Pulse Rifle - 3 Hits At 7 Damage Each

1. Shields absorb 5 - armor absorbs 2 - 0 damage
2. Shields absorb 4 - armor absorbs 2 - 1 damage
3. Shields absorb 3 - armor absorbs 2 - 2 damage

Resulting in a total of 3 shield points and 3 health lost.

1. Shields absorb 4 - armor absorbs 2 - 1 damage
2. Shields absorb 3 - armor absorbs 2 - 2 damage
3. Shields absorb 2 - armor absorbs 2 - 3 damage

Turn 2 results in a total of 3 shield points and 6 health damage.

But what if you used the blaster in turn 1, and then the pulse in turn 2? Following up after the blaster, the second turn of the pulse would look like this:

1. Shields absorb 2 - armor absorbs 2 - 3 damage
2. Shields absorb 1 - armor absorbs 2 - 4 damage
3. Shields down - armor absorbs 2 - 5 damage

A total of 2 shield damage and 12 health damage.

These seem to be sane numbers - not completely broken at least. But since weapons don’t always hit all their shots, the results we see here are highly distorted. Weapons that fire many shots look stronger than they are, weapons that fire few shots appear weaker.

A Closer Look At The Numbers

As we can see in the quick sanity check above, even the average damage numbers are expected to vary from turn to turn - depending on how much shields are left, and how much they recharge. We need a new metric - since calculating average damage per attack or per turn is no longer going to cut it. Instead we should probably try look at how many turns it takes to knock out an enemy.

Creating a script that calculates multiple turns quickly runs into preformance issues as well. One turn of a d12 vs. a d10 has 120 possible outcomes. For two turns that number grows to 14,400. Three turns are 1,728,000 possibilities. For 20 turns that’s a number with 42 digits. For 200 turns the number has 414 digits. The more turns we calculate, the more accurate the number becomes. Since we have to skip all outcomes where the enemy isn’t knocked out at all, we got to do so many turns, that the difference that makes only affects our numbers at a position several digits past the comma. Luckily I got a few programming tricks up my sleeve, that make it possible to calculate hundreds of turns in just a few seconds.

We run into further complications, as the pulse rifle’s average number of hits per turn is only 1.6 - while two of our shields recharge more than that every turn. The pulse rifle can still kill enemies with it’s leak-through damage - but it’s real strength is armor, not shields - and that never comes into play. In practice, groups of players will be fighting groups of enemies, using teamwork and focus fire - thus calculating 1-on-1 isn’t really representative. And it’s actually a good thing, that 1-on-1 duels can be a bit more drawn out and have more potential for comebacks and reversals.

But in order to mimick a group fight and focus fire, we are going to do all calculations for double the number of hits - which is more or less representative of a 2-on-1 situation. These numbers will then show the average amount of turns it takes for two players to take down one enemy. We are also going to just assume everyone has 12 hit points, and we’ll be using three different types of shields:

• fast: size 6, recharge 3/turn
• regular: size 8, recharge 2/turn
• large: size 10, recharge 1/turn

Why these numbers? Well, I actually did try different numbers at first - and then tweak those numbers again and again, until I got satisfying results. It does take many tries to really hone this in, and I’m not trying to hide that - but there’s really no point in me posting dozens of tables with numbers of discarded attempts. I even tried armors with evasion dies of d12, d8, d4 - and shields with only half the recharge rates - just to see what these would look like.

In contrast to the examples further up, shields were always meant to stop auto-recharging once they are depleted. A shield that hits 0 will just stay at 0 until it’s rebooted by a player.

And these are the results we get:

Blaster 7x4	+0	+1	+2	+3	+4	+5	+6	+7	avg.
light.fast	3.42	2.77	2.31	1.96	1.71	1.52	1.38	1.28	2.04
light.regular	3.93	3.14	2.58	2.18	1.88	1.66	1.49	1.36	2.28
light.large	4.33	3.46	2.84	2.40	2.07	1.81	1.62	1.46	2.50
medium.fast	3.46	2.83	2.37	2.03	1.78	1.59	1.44	1.32	2.10
medium.regular	4.25	3.54	3.04	2.69	2.45	2.27	2.15	2.07	2.81
medium.large	4.41	3.67	3.14	2.77	2.51	2.32	2.19	2.10	2.89
heavy.fast	3.97	3.38	2.95	2.63	2.40	2.23	2.12	2.04	2.72
heavy.regular	4.29	3.63	3.15	2.80	2.53	2.34	2.20	2.10	2.88
heavy.large	4.59	3.87	3.36	2.98	2.69	2.46	2.30	2.17	3.05
avg light.*	3.89	3.12	2.58	2.18	1.89	1.66	1.50	1.37	2.27
avg medium.*	4.04	3.35	2.85	2.50	2.25	2.06	1.93	1.83	2.60
avg heavy.*	4.28	3.63	3.16	2.80	2.54	2.34	2.20	2.11	2.88
avg *.fast	3.61	2.99	2.54	2.21	1.96	1.78	1.65	1.55	2.29
avg *.regular	4.15	3.44	2.93	2.56	2.29	2.09	1.95	1.84	2.65
avg *.large	4.44	3.67	3.12	2.72	2.42	2.20	2.03	1.91	2.81
total average	4.07	3.37	2.86	2.49	2.22	2.02	1.88	1.77	2.58

Photon 5x5	+0	+1	+2	+3	+4	+5	+6	+7	avg.
light.fast	3.03	2.47	2.06	1.77	1.56	1.40	1.29	1.20	1.85
light.regular	3.52	2.82	2.33	1.97	1.71	1.52	1.38	1.27	2.07
light.large	4.64	3.83	3.27	2.88	2.61	2.41	2.27	2.17	3.01
medium.fast	2.80	2.30	1.96	1.70	1.51	1.36	1.25	1.17	1.76
medium.regular	3.91	3.30	2.87	2.58	2.37	2.22	2.12	2.05	2.68
medium.large	4.19	3.53	3.07	2.73	2.49	2.32	2.19	2.11	2.83
heavy.fast	3.50	3.04	2.70	2.44	2.26	2.14	2.06	2.02	2.52
heavy.regular	3.84	3.31	2.92	2.62	2.39	2.24	2.13	2.06	2.69
heavy.large	4.01	3.44	3.02	2.71	2.47	2.29	2.17	2.08	2.77
avg light.*	3.73	3.04	2.55	2.21	1.96	1.78	1.65	1.55	2.31
avg medium.*	3.63	3.04	2.63	2.34	2.12	1.97	1.85	1.78	2.42
avg heavy.*	3.78	3.26	2.88	2.59	2.37	2.22	2.12	2.05	2.66
avg *.fast	3.11	2.61	2.24	1.97	1.78	1.63	1.53	1.46	2.04
avg *.regular	3.75	3.14	2.71	2.39	2.16	1.99	1.88	1.79	2.48
avg *.large	4.28	3.60	3.12	2.77	2.52	2.34	2.21	2.12	2.87
total average	3.71	3.12	2.69	2.38	2.15	1.99	1.87	1.79	2.46

Pulse 3x7	+0	+1	+2	+3	+4	+5	+6	+7	avg.
light.fast	2.61	2.14	1.82	1.59	1.42	1.30	1.21	1.14	1.65
light.regular	5.15	4.14	3.46	3.00	2.69	2.46	2.31	2.19	3.17
light.large	5.30	4.30	3.63	3.15	2.82	2.58	2.40	2.27	3.31
medium.fast	3.61	3.11	2.76	2.50	2.32	2.19	2.10	2.04	2.58
medium.regular	4.84	3.97	3.37	2.94	2.63	2.41	2.25	2.14	3.07
medium.large	4.68	3.89	3.34	2.92	2.63	2.41	2.25	2.14	3.03
heavy.fast	3.25	2.85	2.56	2.35	2.20	2.10	2.04	2.01	2.42
heavy.regular	4.06	3.40	2.92	2.58	2.35	2.19	2.08	2.03	2.70
heavy.large	4.60	4.01	3.61	3.33	3.16	3.05	3.00	3.00	3.47
avg. light.*	4.35	3.53	2.97	2.58	2.31	2.11	1.97	1.87	2.71
avg. medium.*	4.38	3.66	3.15	2.79	2.53	2.34	2.20	2.11	2.89
avg. heavy.*	3.97	3.42	3.03	2.75	2.57	2.45	2.38	2.35	2.86
avg. *.fast	3.15	2.70	2.38	2.14	1.98	1.87	1.79	1.73	2.22
avg. *.regular	4.68	3.84	3.25	2.84	2.56	2.35	2.21	2.12	2.98
avg. *.large	4.86	4.07	3.52	3.14	2.87	2.68	2.55	2.47	3.27
total average	4.23	3.54	3.05	2.71	2.47	2.30	2.18	2.11	2.82

I did run the numbers for 1-on-1 attacks as well, and also did some manual and some half-automated playtesting, with actual random dice rolls - including fights where the enemy is shooting back.

We can notice a number of things:

• At a bonus of +2 a victory is highely likely - but not guaranteed.
• Combat is risky and dangerous but not too random. It feels visceral and eventful - and is not just a methodical chipping away at hit points.
• Going from 0 to +1 or from +1 to +2 bonus, is a big step up.
• Photon - the allrounder - is the best weapon individually (not by much), but using a combination of Blaster against shields and Pulse against armor would be even stronger.
• Fast shields are at a noticable disadvantage in a 2-on-1 scenario - but they rock in 1-on-1 or any situation where you can avoid getting hit by multiple attackers each turn.
• Blaster is strongest against light armor, Photon is strongest against medium armor and Pulse is strongest against heavy armor.

all weapons avg.	+0	+1	+2	+3	+4	+5	+6	+7	avg.
avg. light armor	3.99	3.23	2.70	2.32	2.05	1.85	1.71	1.60	2.43
avg. medium armor	4.02	3.35	2.87	2.54	2.30	2.12	1.99	1.91	2.64
avg. heavy armor	4.01	3.44	3.03	2.71	2.49	2.34	2.22	2.17	2.80
avg. fast shield	3.29	2.77	2.39	2.11	1.91	1.76	1.66	1.58	2.18
avg. regular shield	4.19	3.47	2.96	2.60	2.21	2.14	2.01	1.92	2.69
avg. large shield	4.53	3.78	3.25	2.88	2.60	2.41	2.26	2.17	2.99

That leaves us with three types of armors and three types of shields - for a total of 9 possible combinations. All with their own strengths and weaknesses, and all differently suited for different situations.

Creating Additional Items

But having three weapons, three armors and three shields is not enough. It’s a good baseline that we can work off from - and that allows us to flesh things out further, by adding additional items that fit within these now established parameters.

More Armors

I’ve ran the numbers for the potentially two additional types of armors we mentioned last post:

• Stealth armor with protection 0 and an evasive die of D12
• Power armor with protection 4 and an evasive die of D4

And both of them fit just right in and work out overall, with average numbers that stay perfectly in line with the rest. They are both a little unusual though. Stealth armor is pretty strong against weaker enemies (lower bonus) - and pretty weak against enemies with higher bonus. The same would of course also apply to situation with advantage/disadvantage. And Power armor can’t be hurt by Blaster rifles at all - but against Pulse rifles it’s barely even stronger than heavy armor.

I’d go even further and make them more unique by giving stealth armor smaller shields - if any at all - but equip them with optical camouflage instead. And Power armor might give you access to using heavy weaponry, but lock you out of using jet-packs, hacking devices, drone controls and other gadgets.

Armors	protection	evasion	special
Stealth armor	0	D12	optical camouflage
Light armor	1	D10	-
Medium armor	2	D8	-
Heavy armor	3	D6	-
Power armor	4	D4	wield heavy weapons

More Shields

I’ve currently no intention of adding more shields - other than the already mentioned special stealth shield. Running the numbers shows that adding a “Static shield” with a size of 12 and a recharge of 0 would fit in, making that an option that can be considered. Having no built-in recharge rate, this shield would then solely rely on shield healing abilities. But more testing would be required to figure out, how it actually behaves in group combat.

Shields	size	recharge
Fast shield	6	+3/turn
Regular shield	8	+2/turn
Large shield	10	+1/turn
(Static shield)	12	none

More Rifles

Rifles are going to be the main weapon class in the game. A bit like swords, axes and maces in a fantasy game. Just the thing that everyone uses. That’s also why we’ve used three rifles to define our baseline - Blaster, Photon and Pulse.

I’m not a native speaker, so I’m not sure if these actually should be called “rifles” - since they are energy guns (pew-pew) with neither bullets nor rifling? My dictionary only offers “rifle” and “gun” as possible translations though, and “gun” seems to generic as that includes handguns as well.

There is one obvious gap in the existing guns: a weapon firing 4 shots for 6 damage each - and running the numbers, this would indeed work out and fit in fine. But it’s also boring, because unlike Pulse (the armor killer) and Photon (the allrounder), it has no identity and no individual role. So, unless we can come up with something that makes this special, we’ll just keep it in our backhand for later.

Another weapon we do want and have already mentioned earlier, is the beam rifle - a sniper rifle kind of weapon. It will fire just one single shot - but that one shot has to hit hard. We will achieve this, by making it deal full damage against shields. Running the numbers tells us, that 8 is the right amount of damage for this. This still is a rather powerful weapon (especially against high skill opponents) - but we want the beam to be frightful. As a downside it will not be usable at short range, and carefully aiming it long range will give you disadvantage on your evasion roll.

Beam 1x8	+0	+1	+2	+3	+4	+5	+6	+7	avg
light.fast	3.69	3.20	2.86	2.61	2.42	2.29	2.18	2.11	2.67
light.regular	3.69	3.20	2.86	2.61	2.42	2.29	2.18	2.11	2.67
light.large	3.69	3.20	2.86	2.61	2.42	2.29	2.18	2.11	2.67
medium.fast	3.20	2.82	2.56	2.37	2.23	2.13	2.06	2.02	2.43
medium.regular	3.20	2.82	2.56	2.37	2.23	2.13	2.06	2.02	2.43
medium.large	3.20	2.82	2.56	2.37	2.23	2.13	2.06	2.02	2.43
heavy.fast	2.82	2.53	2.32	2.18	2.09	2.03	2.00	2.00	2.25
heavy.regular	2.82	2.53	2.32	2.18	2.09	2.03	2.00	2.00	2.25
heavy.large	4.24	3.79	3.48	3.27	3.13	3.04	3.00	3.00	3.37
avg light.*	3.69	3.20	2.86	2.61	2.42	2.29	2.18	2.11	2.67
avg medium.*	3.20	2.82	2.56	2.37	2.23	2.13	2.06	2.02	2.43
avg heavy.*	3.29	2.95	2.71	2.55	2.43	2.37	2.33	2.33	2.62
avg *.fast	3.24	2.85	2.58	2.39	2.25	2.15	2.08	2.04	2.45
avg *.regular	3.24	2.85	2.58	2.39	2.25	2.15	2.08	2.04	2.45
avg *.large	3.71	3.27	2.97	2.75	2.60	2.49	2.42	2.38	2.82
average	3.40	2.99	2.71	2.51	2.36	2.26	2.19	2.15	2.57

On top of that, we also want a weapon that shoots a spray of tiny plasma pellets - in the style of a shotgun. This Plasgun fires 9 shots, each dealing 1 point of damage. Despite the ability of plasma damage to penetrate armor and ignore protection, this still is the weakest weapon against armor. It’s the strongest weapon against shields though, and that makes it pretty useful, even if it does not seem very impressive overall. It’s only useful a short range though, as it becomes pretty inaccurate at a distance.

Plasgun 9x1	+0	+1	+2	+3	+4	+5	+6	+7	avg
light.fast	5.67	4.60	3.85	3.31	2.92	2.64	2.43	2.28	3.46
light.regular	6.19	4.97	4.12	3.51	3.07	2.75	2.51	2.34	3.68
light.large	6.58	5.28	4.37	3.72	3.24	2.89	2.63	2.43	3.89
medium.fast	4.67	3.87	3.30	2.89	2.60	2.38	2.23	2.13	3.01
medium.regular	5.06	4.15	3.51	3.04	2.71	2.47	2.29	2.17	3.17
medium.large	5.39	4.41	3.72	3.22	2.85	2.58	2.38	2.24	3.35
heavy.fast	3.89	3.30	2.88	2.56	2.34	2.19	2.09	2.03	2.66
heavy.regular	4.18	3.51	3.03	2.68	2.43	2.25	2.13	2.05	2.78
heavy.large	4.45	3.72	3.21	2.83	2.55	2.35	2.20	2.10	2.92
avg light.*	6.14	4.95	4.11	3.51	3.08	2.76	2.52	2.35	3.68
avg medium.*	5.04	4.14	3.51	3.05	2.72	2.48	2.30	2.18	3.18
avg heavy.*	4.17	3.51	3.04	2.69	2.44	2.26	2.14	2.06	2.79
avg *.fast	4.74	3.92	3.34	2.92	2.62	2.40	2.25	2.15	3.04
avg *.regular	5.14	4.21	3.55	3.08	2.73	2.49	2.31	2.19	3.21
avg *.large	5.47	4.47	3.77	3.26	2.88	2.61	2.40	2.26	3.39
average	5.12	4.20	3.55	3.08	2.75	2.50	2.32	2.20	3.22

Next up, we have the Railgun, colloquially known as “the slugger” - for the two heavy tungsten alloy slugs it fires. Like any projectile weapon it is highly ineffective against shields and barely does any shield damage at all. Against armor it’s health damage is comparable to the Pulse rifle. What really makes the railgun stand out though, is it’s high propensity to leak damage through shields. That is also why it’s considered a dastardly weapon, and has actually been banned in some places. It’s also a bit heavy and unwieldy, causing a disadvantage on evasion rolls.

As you may have noticed - the more we go into detail and look at very specific weapon designs, the more this post starts to reference the game I am in the process of designing. These are just the weapons that I came up with - and the descriptions I gave them, and they can be used as examples on how it can be done. When designing your own game - go wild and come up with your own ideas. There’s no mechanical reason for the slugger to be a physical projectile weapon, since mechanically it works identical to all the energy weapons. That’s just a bit of flavor I added to make it feel more unique.

Railgun 2x9	+0	+1	+2	+3	+4	+5	+6	+7	avg
light.fast	2.17	1.84	1.60	1.43	1.30	1.21	1.14	1.09	1.47
light.regular	5.18	4.27	3.62	3.15	2.82	2.56	2.37	2.23	3.28
light.large	6.39	5.26	4.53	4.04	3.71	3.47	3.29	3.17	4.23
medium.fast	3.49	3.03	2.70	2.47	2.30	2.18	2.10	2.04	2.54
medium.regular	5.72	4.79	4.16	3.74	3.46	3.27	3.14	3.05	3.92
medium.large	5.89	4.94	4.29	3.86	3.56	3.34	3.20	3.09	4.02
heavy.fast	3.61	3.08	2.69	2.41	2.23	2.10	2.03	2.00	2.52
heavy.regular	5.90	4.85	4.13	3.67	3.36	3.16	3.04	3.00	3.89
heavy.large	5.43	4.62	4.03	3.63	3.35	3.16	3.04	3.00	3.78
avg light.*	4.58	3.79	3.25	2.87	2.61	2.41	2.27	2.16	2.99
avg medium.*	5.03	4.26	3.72	3.36	3.11	2.93	2.81	2.73	3.49
avg heavy.*	4.98	4.19	3.62	3.24	2.98	2.80	2.70	2.67	3.40
avg *.fast	3.09	2.65	2.33	2.10	1.94	1.83	1.76	1.71	2.18
avg *.regular	5.60	4.64	3.97	3.52	3.21	3.00	2.85	2.76	3.69
avg *.large	5.90	4.94	4.28	3.84	3.54	3.32	3.18	3.09	4.01
average	4.86	4.08	3.53	3.16	2.90	2.72	2.59	2.52	3.29

And that’s all the rifle type weapons for now:

Weapon	shots	damage	type	special
Plasgun	9	1	plasma	ignores armor protection, short range
Blaster rifle	7	4	energy	-
Photon rifle	5	5	energy	-
(unused)	4	6	?	?
Pulse rifle	3	7	energy	-
Railgun	2	9	physical	long range, evasion disadvantage
Beam rifle	1	8	beam	full shield damage, long range, evasion disadvantage

Melee Weapons

In a sci-fi world where ranged weapons with built in targeting computers are the norm and very powerful - melee weapons that require intense training have become more of a somewhat rare specialty. But because of energy shields they aren’t obsolete and can be quite deadly in the hands of a skilled wielder. All melee weapons are plasma weapons - their curved, slender blades are made of expensive cerametal, emitting superheated plasma along their single cutting edge.

Mechanically they do get one single attack, of variable damage. Where the delta does define the number of hits for ranged weapons, it instead defines the damage of the single hit for melee weapons. That means, if you roll a 12 on attack, and your enemy rolls a 1 on evasion (and there’s no bonus in play), then your Plasma sword will deal 11 damage. On average though, even with a +2 bonus, expected damage is more in range of 4 or 5 points. But because it is plasma damage, these swords do cut through armor like butter - completely ignoring the protection. Because of the variable damage, these swords are absolutely devastating against weaker enemies - when the bonus is high.

Using the delta for damage is a design choice I made to differentiate melee weapons, and give them their own special flair. It’s not necessary or required to do that. You could instead have beam weapons behave that way, or come up with another weapon type entirely. There’s also no strong reason, why melee weapons should only have one single attack. They could just as well be based on making multiple swings - and using the delta for number of hits landed. They also don’t have to deal plasma damage. You could have many more different types of melee weapons, behaving in different ways and dealing different types of damage - if you wanted. In my design, melee weapons aren’t super exotic or unheard of, but simply not that common - especially not as a primary weapon.

Plasma sword	+0	+1	+2	+3	+4	+5	+6	+7	avg
light.fast	5.55	4.43	3.63	3.05	2.62	2.29	2.03	1.83	3.18
light.regular	6.11	4.85	3.95	3.30	2.82	2.46	2.18	1.96	3.45
light.large	6.53	5.19	4.23	3.54	3.03	2.64	2.33	2.09	3.70
medium.fast	4.56	3.71	3.09	2.63	2.28	2.02	1.80	1.63	2.72
medium.regular	5.00	4.04	3.35	2.84	2.46	2.17	1.94	1.75	2.94
medium.large	5.35	4.33	3.59	3.05	2.64	2.33	2.08	1.88	3.16
heavy.fast	3.78	3.13	2.65	2.28	1.99	1.78	1.61	1.49	2.34
heavy.regular	4.12	3.40	2.87	2.46	2.15	1.91	1.73	1.59	2.53
heavy.large	4.41	3.65	3.08	2.65	2.32	2.06	1.86	1.70	2.72
avg light.*	6.06	4.82	3.94	3.30	2.82	2.46	2.18	1.96	3.44
avg medium.*	4.97	4.03	3.34	2.84	2.46	2.17	1.94	1.75	2.94
avg heavy.*	4.11	3.39	2.87	2.46	2.16	1.92	1.73	1.59	2.53
avg *.fast	4.63	3.76	3.12	2.65	2.30	2.03	1.82	1.65	2.74
avg *.regular	5.08	4.10	3.39	2.87	2.48	2.18	1.95	1.76	2.98
avg *.large	5.43	4.39	3.64	3.08	2.66	2.34	2.09	1.89	3.19
average	5.05	4.08	3.38	2.87	2.48	2.18	1.95	1.77	2.97

I do imagine these to look like sci-fi swords inspired by Japanese designs - Katana, Naginata, Odachi, etc. - but there’s little reason a player could not have gotten a custom made different blade shape or style.

One Handed Versions

Creating one handed versions can be easy, but also a real challenge.

I want to allow players to have a primary weapon and a secondary weapon - with only one-handed weapons being allowed as secondaries. There is no penalty or cost associated with swapping, so players can always use whichever of the two weapons they prefer. The primary could then either be a two handed weapon, or a deflector disc (handheld physical shield) plus a one-handed weapon. One-handed weapons should deal somewhat less damage than two-handed ones, but still be useful. If your primary is weak against armor, or can attack at close range, you will want a secondary that can fill that gap.

Weapon	+0	+1	+2	+3	+4	+5	+6	+7	avg
Short Plasgun 5x1	5.92	4.97	4.29	3.80	3.45	3.19	3.00	2.88	3.94
Blaster pistol 4x4	5.24	4.44	3.87	3.45	3.16	2.95	2.80	2.70	3.58
Photon pistol 3x5	5.48	4.59	3.98	3.54	3.24	3.03	2.88	2.78	3.69
Pulse pistol 2x7	7.81	6.29	5.29	4.64	4.21	3.91	3.71	3.58	4.93
Plasma blade (max 5)	5.92	4.97	4.29	3.80	3.45	3.19	3.00	2.88	3.94

Easy enough, right? Pulse pistol may seem a bit weak - but that’s only because 2 shots are super inefficient against shields - it’s still strong against armor.

But if you now want to allow dual wielding, then all hell breaks loose. I know, dual wielding ranged weapons is kinda ridiculous and unrealistic - but players love it, and it does increase build diversity. So, generally it would be a desirable feature to have. But shooting two Pulse pistols is not the same thing as shooting one 4x7 rifle. Because of how much easier it is to land one or two hits, compared to three or four, dual wielding any of these pistols is completely overpowered.

Reducing the attack die to a D10 or even a D8 when dual-wielding (as an accuracy penalty) is by far not enough to fix that. The single pistol would have to be excessively weak - to make it balanced for dual wield. The only way I found to make this work, is to have both weapons run off a single shared attack die, and then still reduce that to a D10. That means, that dual wielding two Blaster pistols 4x4 technically works like wielding one 8x4 rifle that uses a D10 for attack.

Weapon	+0	+1	+2	+3	+4	+5	+6	+7	avg
2x Short Plasgun 5x1	6.97	5.31	4.21	3.46	2.94	2.56	2.30	2.11	3.73
2x Blaster pistol 4x4	5.42	4.16	3.33	2.76	2.37	2.09	1.89	1.74	2.97
2x Photon pistol 3x5	4.59	3.56	2.89	2.43	2.11	1.89	1.74	1.63	2.60
2x Pulse pistol 2x7	4.18	3.29	2.70	2.31	2.05	1.87	1.75	1.67	2.48

Look at how strong the pulse pistol is, all of a sudden. It suffers the most from being reduced to 2 shots - and profits the most from being increased to 4 shots.

That same approach would theoretically also work for the plasma blade - simply cap it at 10 damage, instead of max 5 - but since we swapped hits for damage here, that feels really unlogical to me. For pistols it’s explainable that you roll one die, and the resulting delta tells you the total number of hits you do across both guns. But when dual-wielding blades, it really doesn’t make much sense to have just one hit that does twice as much damage.

Let’s have dual wield melee actually roll two D10 (or roll just one - but use it twice), and each one of those attacks does max 4 damage individually:

Weapon	+0	+1	+2	+3	+4	+5	+6	+7	avg
2x Plasma blade (max 4)	4.64	3.78	3.18	2.78	2.51	2.32	2.19	2.11	2.94

This sadly has turned into a bit of convoluted mess now. The clean and simple solution would definitely be to just not allow dual wield at all. I will probably keep this as an optional rule only, and leave it up to the game master to decide whether they want to include it or not.

Heavy Weapons

These might or might not eventually get limited to be used with power armor only. Heavy weapons are supposed to offer area of effect options that allow for attacking multiple enemies at once, and when doing so (not against single enemies though), have a damage potential that goes beyond that of rifles. They all cause disadvantage on evasion rolls.

The idea here is, that the player rolls a single attack roll of a D10 - which is then applied to multiple enemies (up to three - all within reach of the weapon) individually. We want the damage potential against one single target to be weaker than a rifle - but against multiple targets, it should do more damage in total. The approach is similar to dual wielding blades.

That means, for the damage against each individual enemy, we can just re-use the same stats as for pistols.

• Flamethrower 15x1 - per target (up to 3): 5 shots x 1 plasma damage
• Turboblaster 12x4 - per target (up to 3): 4 shots x 4 energy damage
• Heavy Photon 9x5 - per target (up to 3): 3 shots x 5 energy damage
• Arc gun 3x6 - per target (up to 3): 1 shots x 6 electrical damage

The Flamethrower is mechanically identical to the Plasgun, and the Arc gun shots arcs of electricity which do full shield damage (just like the beam). Both are short range only.

Other Items

Other things, like energy beams to recharge shields, the deflector discs mentioned above, psionics, buffs and debuffs, hacking devices, drones and drone control, and more; are planned as well, but much more closely tied into the skill system. As far as combat is directly concerned, those listed further up are the only items we have to look at now.

Thrown weapons like for example grenades might be interesting to look at as well - but this post is long enough as is, so that will have to wait until another time as well. The same goes for additional damage types like for example ion damage, which probably should do full shield damage, zero armor damage, and be able to temporarily disable shield recharge. And of course, ion grenades would be interesting too!

I currently have no plans to create any form of martial arts - but it would be possible to say that energy shields do not work on kicks an punches, allowing martial arts to actually be viable in a world full of energy weapons, simply because it completely ignores shields.

Psionics are planned to be subtle mind effects - mostly resulting in advantage/disadvantage buffs/debuffs. It’s not going to be possible to prove beyond any doubt, that psionic powers actually exist - because they only produce these subtle effects, that could always be coincidence as well.

Hacking is going to be mainly about opening locks, disarming traps and disabling alarms - but will also have combat applications, like marking an enemy, disabling stealth, boosting shields, disabling recharge, etc.

And drone control will allow for what basically are like robotic pets. Flying drones will have high evasion and no protection - and only be able to have pistols integrated. Ground based drones will be robotic walkers, and be able to carry integrated rifles. Finally, turrets will be able to follow their master on tracks - but for combat they’ll have to be deployed and become stationary, allowing them to use heavy weapons. Giving a command to a drone (“Shoot enemy X”) is an action, but the drone will then continue to follow that command autonomously until stopped, or given a new command.

Conclusion

We have created a fairly deep and intricate combat system, that is still relatively easy to handle, and has fast-flowing turns that require only very few die rolls. We managed to design a combat systems that feels visceral and isn’t about chipping away at hit points - while still having rather predictable outcomes overall, and not being too random.

We have created:

• 5 different sets of armor
• 3 (potentially 4) different energy shields
• 7 different two-handed primary weapons (including a melee option)
• 5 one-handed versions of these
• 4 heavy weapons
• a deflector disc (handheld shield)
• the possibility to dual wield

And most importantly, all of these feel unique and different to each other. They are all sidegrades - not better or worse versions of the same, and can be combined in any way the player wants. All choices have their individual and situational strengths and weaknesses. And that’s still without the skill-related stuff like psionics, hacking, drones, energy transfer, etc.

You may also have noticed, how having a mathematically solid and well thought-through base helps when building on top of it. Stuff just falls into place, and you can often achieve extra depth without needing extra rules and mechanics.

Next time we are probably going to look at characters, skills, health and wounds, XP and progression, and everything related to that. Until then!