FMA DSII

7 posts ยท Oct 1 2001 to Oct 2 2001

From: Oerjan Ohlson <oerjan.ohlson@t...>

Date: Mon, 01 Oct 2001 19:04:36 +0200

Subject: RE: FMA DSII

> Brian Bell wrote:

> Thanks for your critique!

You're welcome :-)

> One of the things that I have considered is to require both the

I haven't had time to look at this fully yet, but it could work.

> I wrote:

> There is another DS-FMA system in testing, based on what Jon posted on

Jon has given the OK now, so here goes. I hope the various tables come
through more-or-less readable... but I don't expect them to <sigh>

********
Initial notes:

1. This is one possible idea of how the DS3 FMA damage system might work.
There's no guarantee whatever that the final product will look anything like
this!

2. These rules are deliberately designed to use multiplication, because it
gives the probability distributions I want (and also because it takes me
considerably less time to multiply two numbers than to add five numbers
together <g>). When it says "the firer rolls an Impact die and multiplies the
result with the weapon's size class", it means exactly that. It very
emphatically does NOT mean "roll a number of impact dice equal to the weapon's
Size Class and add the results together."!

3. For the purpose of these rules, "heavy weapons" include all DS2 weapons
which have a chance to damage targets with armour/1 or more in DS2 from
the front. (In other words, everything but infantry rifles and APSW. The jury
is still out on HEF artillery rounds though.)

********
IAVR changes:
IAVRs now roll 1D8 to hit; the target is hit on rolls of 3+.
IAVR warheads count as size class 3 (same as GMS/L).
[See below for why.]

********
Heavy weapons fire against armoured vehicles: After scoring a hit by whatever
game mechanic is appropriate for the weapon, the firer rolls an Impact die and
multiplies the result with the weapon's size class while the target rolls 1D8
and multiplies with the target's armour rating.

If the final Impact score EXCEEDS the final Armour score, the target is
destroyed. [This means that soft-skinned vehicles are always destroyed
if
hit by a heavy weapon - they multiply their Armour die with 0. This is
the reason for the IAVR modifications; without them they'd *automatically*
kill
any soft-skinned targets within range.]

If the final Impact score does NOT exceed the final Armour score BUT the
Impact die rolled its MAXIMUM VALUE (eg. a D6 rolling a "6" or a D10 rolling a
"10"), the hit has inflicted Special Damage. Roll a D8:
1-3: Mobility hit
4-5: Systems Down: Target
6-8: Damage

If the final Impact score does NOT exceed the final Armour score and the
Impact die rolled LESS than its maximum value, the hit inflicts no significant
damage.

********
Fire against infantry, and infantry fire vs. softskinned vehicles: When
shooting at infantry, you don't have to roll to hit. Just roll the Impact and
Armour dice and multiply by the appropriate factors; if the final Impact score
EXCEEDS the final Armour score the infantry target is destroyed. Special
Damage does not apply to infantry targets.

Armour/0 vehicles count as "PA" when fired at by non-heavy weapons,
except that Special Damage results DO count against them.

Note that most heavy weapon types have a fixed Impact multiplier against
infantry, independent of their Size Class (see the tables below). Eg., a
HEL/1 and a HEL/5 both roll 1D4x2 for Impact against infantry.

********
Heavy weapon Impact die types:

Range: All size classes Weapon Close Med Long vs. Infantry (1): HEL
- vs ablative   D4      D4      D4      n/a
- vs other      D8      D8      D8      D4x2
HVC D10 D8 D4 D4x2 RFAC D10 D6 D4 D4x2 MDC, HKP D12 D10 D8 D4x2 (2) DFFG (3)
D12x2 D12 D6 D6x3 HEAT (4)
- vs reactive   D6      D6      D6      n/a
- vs APFC (6)   D4      D4      D4      n/a
- vs other      D10     D10     D10     D4xSize (5)

(1) The Impact multiplier vs. infantry is fixed for most weapons. Eg., a
HEL/1 and a HEL/5 both roll D4x2 against infantry, rather than D4xSize
Class. (2) HKP cannot damage infantry
(3) Yes, a DFFG/5 at close range rolls 1D12 for impact and multiplies by
2x5 = 10. This is *weaker* than it is in the chit system... (4) "HEAT"
includes GMS, IAVR and SLAM. Of course these types may use other types of
warheads in the future, but in DS2 they all have the same type of warhead and
their ancestors of today have HEAT warheads so I use that
"collective" name for all of them :-7 GMS/H = size class 5, GMS/L and
IAVR = size class 3. (5) SLAM only. GMS and IAVR cannot damage infantry. (6)
IAVR only. This supercedes any reactive armour the target might have.

(Yes, "Red" chit validity can translate as both D6 and D8.)

********
Infantry weapon Impact die types:

Combat type: Target is... Firefight: Close Assault: In the open D10 D12 Soft
Cover D6 D10
Dug In/Urban    D4              D6

Impact multipliers: Line and Militia: x2 PA, APSW (and Assault Teams in CA) x3

Infantry "Armour ratings": Militia: 3 Line: 4
PA, armour/0:   7 (Yes, seven. No, this is not a typo.)

********
Artillery impacts: Target:
Ammo:   Vehicle:        Vehicle,                Inf:    Inf., dug-in:
                         dug-in
HEF D4 No effect D10 D6 MAK D10 D6 D4 No effect

Artillery Impact multipliers: Target: Type: Vehicle: Infantry: Light 1x 2x
Medium 2x 3x Heavy 3x 4x

********
Final notes:

First off, big kudos to Mikko Kurki-Suonio for analysing the DS2 chit
draw system. That saved me a *lot* of work (as Brian recently found out <g>).

This system attempts to emulate the results of the DS2 chit system. It is by
no means an exact match; for example the QDS generally gives a higher
number of kills but a fewer damaged targets (except for size/1 weapons
shooting at very well-protected targets). In addition the "Systems Down:
Firer" results have been eliminated from the damage resolution. It does
however keep the "flavours" of the various weapon families relatively intact.

What I've done is to try to get get the value

P(kill) + P(special damage)/2

for the QDS to be as close as possible to the value

P(kill) + P(both M and SD:T damage) + (P(damage and/or no more than one
of
SD:T and M))/2

for the chit system, while still having all weapon sizes within a single
family use the same Impact die type in a given range band. (Fortunately for
me, RFAC and HVC have different names so can be considered as different
families! <g>) In the infantry case I've just looked at the straight P(kill)
- infantry doesn't take any special damage, after all. As you can see, I
consider vehicles which can neither shoot nor move to be "destroyed" -
while they might be salvagable after the battle, they have been knocked out
for the time being...

Playests so far suggest that HELs, HVCs and size class/1 weapons from
the other families have gained a little in lethality while most others have
lost a little, particularly at close range. OTOH, this reduced lethality
compensates for the eliminated risk for SD:F results which plagued the larger
size classes in the chit draw system! Reactive and Ablative armours also seem
to have gained a little in efficiency.

The "Special Damage" mechanic gives even small weapons a chance to hurt
heavily armoured targets - as a (real-life) designer of light
anti-armour
weapons I feel that that's important! <g> Note that there are NO "BOOM" or
"Systems Down: Firer" results - the former is unnecessary since the
"standard" kill mechanism (ie., exceeding the Armour score) gives more
kills than the "standard" chit-draw kill (getting enough valid numerical
chits), and IMO the latter belongs in the to-hit mechanism rather than
in
the to-damage mechanism.

Some playtesters have asked why the QDS doesn't use the "if Impact and Armour
scores are equal, the target is Damaged" mechanic. The reason is that the
probability to inflict such a result varies very "unpredictably" from one
weapon class to another one size class of a certain weapon family could have a
25% chance to inflict a Damage result against a certain armour
die/class, the next bigger one 0%, and the next bigger again 10%... not
a good thing IMO. A variant of this is "if Impact and Armour DICE (ie., before
multiplication) values are equal, the target is Damaged", but this hurts the
small low-impact weapons badly and it makes it completely impossible to
get a "Damage" result if the weapon's Size Class is bigger than the Armour
Rating (even if the weapon is low-impact).

Later,

From: Roger Books <books@m...>

Date: Mon, 1 Oct 2001 14:09:57 -0400 (EDT)

Subject: Re: FMA DSII

> On 1-Oct-01 at 13:10, Oerjan Ohlson (oerjan.ohlson@telia.com) wrote:

> <Big snip>

Hey, this is exactly what I was looking for, it gives the SG feel I was after
while working with DS and doing away with the chit system. We are playing DS
Wednesday, I'll see if I can convince my newbies players to give it a try.

Hmmm, looking at it I have one minor difficulty, HEAT vs APFC's do a system
down 25% of the time? I'm having trouble rationalizing it.

From: Oerjan Ohlson <oerjan.ohlson@t...>

Date: Mon, 01 Oct 2001 21:40:56 +0200

Subject: Re: FMA DSII

> Roger Books wrote:

> Hey, this is exactly what I was looking for, it gives the SG feel

Having the hull shovered with shrapnel from the round your APFC blasted
fifteen meters away from the tank isn't all that healthy for your sensors <g>

And it's not "systems down 25% of the time" - SD is the least likely of
three possible Special Damage outcomes, and if you kill the target you
don't score any Special Damage at all :-)

Besides, since I design LAWs/IAVRs (AT4/M136, etc) for a living I'm
slightly  biased in their favour ;-)

Seriously though, I know exactly what you mean. It *is* annoying that IAVRs
firing at Armour/4 or stronger targets have a marginally better chance
to inflict at least some damage if the target has APFC than if it has RA, even
though the APFC-equipped target runs a lower risk of actually getting
*destroyed* than the RA-equipped one.

For example, here are the outcomes for IAVRs hitting Armour/5 targets
with...
No specials RA APFC No effect 62% 71% 68% Immobilized 1.5% 3.8% 7% Damage 1.5%
3.8% 7% Systems Down 1% 2.5% 5% Kill 34% 19% 13%

I could get around this by giving HEAT Impact D8 against RA, but that makes RA
rather weaker than in the chit system... and, equally important, it
doesn't really solve the *percieved* problem - ie. those players who
look
at the IAVR-vs-APFC interaction without crunching *all* the numbers and
say
"Special damage 25% of the time?!?" :-7

Later,

From: Richard Kirke <richardkirke@h...>

Date: Mon, 01 Oct 2001 19:49:59 +0000

Subject: Re: FMA DSII

Ooops it apears that I have the wrong end of the stick!

Sorry

From: Richard Kirke <richardkirke@h...>

Date: Mon, 01 Oct 2001 19:50:06 +0000

Subject: Re: FMA DSII

Ooops it apears that I have the wrong end of the stick!

Sorry

From: Roger Books <books@m...>

Date: Mon, 1 Oct 2001 16:00:11 -0400 (EDT)

Subject: Re: FMA DSII

> On 1-Oct-01 at 15:43, Oerjan Ohlson (oerjan.ohlson@telia.com) wrote:

> I could get around this by giving HEAT Impact D8 against RA, but that

Actually I'm more worried about those that go "Hmmm, I have to put a class one
weapon on which will rarely hurt a tank. Let's pick one that rolls a small die
because then I have a better chance of getting a special."

From: Oerjan Ohlson <oerjan.ohlson@t...>

Date: Tue, 02 Oct 2001 20:06:26 +0200

Subject: Re: FMA DSII

> Roger Books wrote:

> >I could get around this by giving HEAT Impact D8 against RA, but that

Same players, same problem. Drawing quick conclusions from first impressions
without looking at *all* the relevant numbers involved can
often lead you astray :-)

Let's take a closer look at the case you describe above:

At first glance, it seems obvious that a low-Impact weapons will score
significantly higher number of Specials against heavy targets. Indeed, that
was my first reaction when I first started testing these rules.

However... in order to get a noticable better chance of getting a special,
you need a Class/1 with Impact D4 firing at an Armour/4 or stronger
target. If the lower Impact die scores slightly more special hits but fewer
(or no) kills, you tend to notice the fewer kills far more than the extra
specials;
for DS2 armour levels the Class/1, Impact D4 is the only combination
where I've found the number of extra Specials to stand out compared to the
reduced number of kills.

Impact D4 gives you two options:

* HEL/1, but only if the enemy cooperates by using Ablative armour

* RFAC/1, but only at Long range (ie. 12-16")

The HEL/1 has a very nice feature: it is by far the longest-ranged and
most
accurate class/1 weapon in the game. IMO its potential ability to
inflict Specials comes a distant second after this. The main drawback of the
HEL/1
is its lack of hitting power up close, and it is also fairly expensive, but
all in all I consider this the most versatile of all the class/1 weapons
in
DS2 - under the chit system as well as under this one.

The RFAC/1 is the cheapest heavy weapon in the game, but that's about
the nicest thing you can say about it. If someone picks it instead of an
MDC/1
*only* because of its higher ability to inflict Specials on heavily
armoured targets, I'd say that he is fooling himself: Yes, the RFAC/1
inflicts more Specials on targets with Armour/4 or more (1) at range
12-16", but the MDC/1 is as good or better (2) - usually better -
against all targets outside this rather narrow range band, and against targets
with
Armour/3 or less even in the 12-16" range band. The MDC/1 also has 50%
longer range than the RFAC/1 (24" vs 16").

(1) If you look at the same number shots which actually *hit the target*,
the RFAC/1 inflicts more damaging hits against Armour/3 as well. Since
however the 12-16" band is Long range for RFAC/1 but Medium range for
the
MDC/1, the MDC/1 scores enough extra hits to roll damage for that it
inflicts more damage for a given number of shots *fired* against
Armour/3
targets.

(2) "better" as in "inflicts a larger total number of Specials and Kills, OR
inflicts the same total number of Specials and Kills but with a larger ratio
of Kills to Specials". I tend to consider a Kill to be more useful

than a Special <g>

So, well... in DS2, I don't think that you'll see these high numbers of
Specials very often - if you see them at all. If DS3 allows more
flexible
armour layouts and/or higher armour levels on relatively small vehicles
this quirk may become more of a real problem though.

Please let me know if you use this system, and any post-game reactions
:-)

Later,