[[[Playtest Focus]]] New Missile Rules

MongooseMatt

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Okay chaps, take a look at the rules below, a set of mechanics designed to handle multiple missiles with a single roll, while streamlining countermeasures taken against them.

This is a revision for the Core Rulebook, which will obviously have an impact on High Guard, but we must start at the beginning.

Let me know of any issues you can see and, hopefully, we can make these rules (or something close to them!) official. I would like to achieve consensus on these rules by the end of the weekend if possible...



Missiles

[[[ Replace text on pages 161-162 ]]]

Missile Combat
Unlike most weapons which travel at or close to the speed of light and so hit enemy ships almost instantly, missiles take time to cross the gulf of space. However, despite this drawback, missiles are capable of doing a great deal of damage when they hit an enemy ship.

Launching Missiles
Missiles cannot be used against targets within Adjacent or Close ranges, as there is not enough time for them to obtain a solid lock and safety protocols are engaged to stop the, turning back and hitting their own launch vessel.

Missiles are launched in salvos. A salvo is all the missiles launched by a ship against a single target in the same combat round. This could be a single missile from one turret or dozens from multiple turrets or bays (see High Guard for more information on weapon bays).

Missile salvos effectively have a Thrust of 10 and will reach their target a number of combat rounds after they have been fired, as shown on the Missile Flight table.

Missile Flight
Range Rounds to Impact
Close and Short Immediate
Medium 1
Long 2
Very Long 3
Distant 5

Note that while missile salvos can be fired at Distant ranges, the attacking ship must have detected its target before they can be launched. Given the limited information that can be gained from sensors at this range, friendly fire incidents may be common among Travellers who are too trigger happy with their missiles.

If a missile has not reached its target within 5 rounds, it will run out of fuel and become inert.

Missiles and Targets
When a missile salvo reaches its target, the missile makes an attack roll as normal. However, the Gunner skill of the Traveller(s) that fired the salvo is not used as a DM.

Instead, the number of missiles in the salvo greatly affects their chances of making a successful attack. Apply DM+1 to the attack roll for every full 5 missiles in the salvo.

Note that missiles almost always have the Smart trait (see page 75). For missiles, use the TL of the missile itself or that of the attacking ship, whichever is greater.

Finally, missiles launched at Distant range expend most of their fuel just reaching their target, leaving little to counter the target’s manoeuvres. Missile salvos launched at Distant range suffer DM-6 to their attack rolls.

Impact
If an attack roll for a missile salvo is successful, the target will sustain damage. If the salvo consists of just a single missile, this is performed as normal.

However, if a salvo consists of more than one missile, do not add the Effect to the damage caused. Instead, add 1D of damage for every point of Effect. This represents the increased damage of multiple missiles striking their target.

Variant Missiles
High Guard introduces different types if missiles that are more accurate, carry more fuel or are faster, but these rules suit all missiles included in this Core Rulebook. If a ship launches different types of missile at the same target in the same round, then all the missiles of each type are counted as a different salvo.

Electronic Warfare
A Traveller performing sensor operator duties on a spacecraft can use the Electronic Warfare action to destroy or misdirect incoming missiles before they impact his vessel or another ship within Close range.

The sensor operator must succeed at a Difficult (10+) Electronics (sensors) check (1 round, INT) in order to destroy or render inert incoming missiles within a single salvo. The Effect of this check is applied as a negative DM to the salvo’s attack roll when it reaches the target.

Note that a negative Effect on the Electronics (sensors) check will give the salvo a bonus to hit – the sensor operator has made a critical mistake and effectively broadcast the position of his ship, giving the missiles a better electronic profile to attack!

Electronic warfare may be performed upon a salvo multiple times over several rounds, with the effects being cumulative. However, a salvo may only be subjected to electronic warfare once per round, no matter how many sensor operators are available.

Long Range Launches
At extreme ranges, combat involving missiles creates a very different atmosphere. The target spacecraft will likely have detected the launches and its crew will have several tense minutes to watch the blips on their sensor screens gradually get closer and closer.

Fortunately, the crew need not be idle as they await their destruction as there are several countermeasures that can be taken against incoming missiles.

Electronic Warfare: A sensor operator may engage in electronic warfare once every round, following the rules above.

Flee: A spacecraft under missile attack may simply turn around and engage its manoeuvre drive, thrusting away from the missiles. Missiles are extremely long-ranged weapons and so it is not normally possible to outrange a missile in this way, but it can perhaps buy enough time to prolong electronic warfare or make a jump.

Point Defence: Finally, just as a salvo is about to strike, gunners may engage in point defence, as detailed on page 160.



[[[ Replace text on page 160 ]]]

Point Defence (Gunner)

Using a turret-mounted laser (beam or pulse), a gunner can destroy incoming missiles. Note that a weapon used for point defence cannot be used to make attacks in the same combat round, and vice versa. Point defence may only be performed against missile salvos (see page 161) as they are about to make their attack roll against a target – missiles are too small and too fast to be targeted at greater ranges.

The gunner must succeed at a Gunner (turret) check against any missile salvo that is about to make its attack roll against his spacecraft. If the salvo consists of a single missile, a successful check will automatically destroy it. Otherwise, the Effect of the check is used as a negative DM applied to the missile salvo’s attack roll. Note that, unlike electronic warfare (see page 162) a failed Gunner (turret) check will not provide the missile salvo with a bonus to its attack roll.
 
A first question please Matt. Does the thrust of the launching vessel add to the speed of the missiles i.e. a M9 ship + missile thrust 10 = thrust 19 actual speed?

If it doesn't, what happens when you have a reaction drive driven ship that launches say already doing thrust 15? Do they over run their own missiles? (obviously not one might assume??!)

And if the thrusts add then this should be stated and the consequences noted = the missiles get to hit quicker closing the range bands in some amount of rounds per thrust level, and the target needs a superior speed to run away from them... along with anything else... harder to evade??
 
That has been the elephant in the room :)

I really don't want to mess around with missile timings and launching ships imparting kinetic energy to them because things are going to start getting really complicated really quickly...
 
One suggestion then. How about dropping the Distant range band on standard missile and the resultant complications and just leave missiles moving in at a 3 turn Very Long range max. That's a reasonable fudge with regards speed in that you can easily state even a significant increase in thrust is not going to affect how much quicker than 3 turns a missile is actually going to reach the target (and there would be other issues as well like stabalizing a firing platform and flight path changes as the missiles adjust to target movement). The 10 thrust can be stated as an 'effective' thrust rating to assist the rules interpretation if the target ship is running away from them.

What you could do then is put in a high thrust version of missiles in High Guard that can be used at Distant range but with it's own range band progress table say 1,1,2,3 and a stated thrust of 15 or as best suits.
 
That is one way of doing it - at the moment, we simply have a negative DM to represent the difficulties of Distant targeting.

What does everyone else think? Remember, complexity with missiles is a Bad Thing, but we want to get it right!
 
Note that a weapon used for point defence cannot be used to make attacks in the same combat round, and vice versa.

I note that this does not say " a turret used for point defence...". So does it need to be defined what happens with a point defence of multiple weapons in the same turret? Either of the same type (3 lasers - do they all get a roll, can they add for hit or increased Effect?) or mixed (2 missiles and a laser - can you fire the missiles offensively and have the laser for defence in the same round: very important). It might help to clarify this specifically.
 
That looks very clean.

I see a slight problem with scaling. If I toss one or two missiles at a Scout with skilled crew, it will probably not hit just because of EW. If I toss 1000 missiles at a warship; EW, Armour, and Range DM becomes irrelevant.

I guess the 1000 missile case will disappear into the capital ship combat system.

Example: Two 400t warships with professional Navy crews are shooting at each other at Very Long range, two missile turrets, two triple laser:
Fire 6 missiles, EW, EW, EW, PD, PD, Attack, Damage
Launch is 2D +2(skill) +1(DEX) +3(FireControl) -8(Average) ≈ 5 Effect
EW is 2D +2(skill) +1(INT) +6(Sensor) -10(Difficult) ≈ 6 Effect
PD is 2D +2(skill) +1(DEX) +2(triple) -8(Average) ≈ 4 Effect
Attack is 2D +5(many missiles) +5(Launch effect) -6(EW) -6(EW) -6(EW) -4(PD) -4(PD) -2(EvasiveAction) -2(Evade software)≈ 7 +10 -30 ≈ Effect -13, very much missed.

OK, make that 3 missile turrets and 1 laser turret:
Launch is 2D +2(skill) +1(DEX) +3(FireControl) -8(Average) ≈ 5 Effect
EW is 2D +2 (skill) +1(INT) +6(Sensor) -10(Difficult) ≈ 6 Effect
PD is 2D +2(skill) +1(DEX) +2(triple) -8(Average) ≈ 4 Effect
Attack is 2D +8(many missiles) +5(Launch effect) -6(EW) -6(EW) -6(EW) -4(PD) -2(EvasiveAction) -2(Evade software) ≈ 7 +13 - 26 ≈ Effect -6, still miss.
Damage is 4D +8D +0(Effect) -10(Armour) ≈ 32 which is about 20% of structure so an additional two crits. Not unreasonable.

OK, degrade the sensor to +0:
Launch is 2D +2(skill) +1(DEX) +3(FireControl) -8(Average) ≈ 5 Effect
EW is 2D +2 (skill) +1(INT) +0(Sensor) -10(Difficult) ≈ 0 Effect
PD is 2D +2(skill) +1(DEX) +2(triple) -8(Average) ≈ 4 Effect
Attack is 2D +8(many missiles) +5(Launch effect) -0(EW) -0(EW) -0(EW) -4(PD) -2(EvasiveAction) -2(Evade software) ≈ 7 +13 - 8 ≈ Effect 12, automatic crit.
Damage is 4D +8D +12(Effect) -10(Armour) ≈ 44, almost 30% of structure so 2-3 crits more.

We have very large modifiers on the small random range of 2D. Sensor DM completely dominated the result, but that will shrink at shorter range.
Adventure class ships are, as usual, completely helpless against even very small warships.


Nitpicking:
The missile launch is a Average? Gunner, [DEX,EDU?] task (remember the effect) task, that should probably be mentioned explicitly.

The PD Reaction should probably be a well defined task, e.g. "The gunner must succeed at a Average Gunner (turret), DEX check against any missile salvo..."
 
I was thinking that, to counter EW and PD with more than just weight of numbers, we would need some skill bonus at the firing end (currently there is none). I _was_ thinking some kind of 'Missile Solution Software' to handle this... But I want to see what everyone thinks first.

The other counter is to increase the DM from the number of missiles, but that is a bit of a hammer blow approach.
 
Another example:
Two Free Traders with two turrets with 2 missile racks and a laser each.
Civilians so less skilled gunners and less software.
Fire 4 missiles, EW, EW, EW, PD, PD, Attack, Damage
Launch is 2D +1(skill) +1(DEX) +1(FireControl) -8(Average) ≈ 2 Effect
EW is 2D +1(skill) +1(INT) -2(Sensor) -10(Difficult) ≈ -3 Effect, so don't...
PD is 2D +1(skill) +1(DEX) -8(Average) ≈ 1 Effect
Attack is 2D +3(many missiles) +2(Launch effect) -1(PD) -1(PD) -2(EvasiveAction) ≈ 7 +5 -4 ≈ Effect 8, crit!
Damage is 4D +3D +8(Effect) -3(Armour) ≈ 30 around 37%, so a few more crits. Deadly.
 
msprange said:
I _was_ thinking some kind of 'Missile Solution Software' to handle this...

The disadvantage is that civilians won't have the computers to run additional software, further crippling your average Scout/Free Trader.

You could halve the sensor DM, they are rather large for a 2D DM.
 
AnotherDilbert said:
The disadvantage is that civilians won't have the computers to run additional software, further crippling your average Scout/Free Trader.

I might be okay with that - creating a kind of 'two tier' missile combat...
 
AnotherDilbert said:
That looks very clean.

I see a slight problem with scaling. If I toss one or two missiles at a Scout with skilled crew, it will probably not hit just because of EW. If I toss 1000 missiles at a warship; EW, Armour, and Range DM becomes irrelevant.

AnotherDilbert beat me to it. You kind of invalidate everything with 10, 100 or 1000 missiles being tossed. The biggest problem Matt is that everything becomes hit or miss - for 1 missile or 10,000 torpedoes.

While I do like the approach of making everything a modifier to cut down on rolls, I think we will have to do it a different way to avoid the crazy "1000 missiles miss you or hit you!" - and it would be a zero-effort fit for High Guard too.

A) Launch missiles (no roll)
B) Apply mods for EW, range, etc..
C) Rather than rolling for the missiles to hit, roll on some table (with the mods for EW, range, pd operator skill, etc) to see how many missiles of the incoming salvo are destroyed/intercepted.
Simply have a table with values ranging from lets say 0.1 to 5.0. Thats how many missiles are intercepted per each weapon on point defense.
D) Then roll normally for remaining missile damage as per normal. For smaller salvos, this is trivial - just like being hit by like 4 or 5 pulse lasers. (For larger salvos, this can flow seamlessly into your mass-capital-combat rules, as you would replace this with whatever formula you have for, for example, being hit by 1000 beams)

Simple way to have 1 roll, give you a realistic gradient to determine how many missiles actually hit you out of the 10s, 100s or 1000s fired. In essence - I think your approach is perfect - but it creates that unwanted binary solution that will always be a problem if you're rolling "to-hit" with 1 whole salvo. Instead, our "roll" should be - "how much of the salvo survives my defences?"
 
How about something like:

A) Launch missiles (no roll)
B) Apply mods for EW, range, etc..
C) Roll ( 2D + AttackDMs ) * 10% of missiles hit (max 100%, round down)
D) PD: remove calculated number of missiles per PD mount. (no roll)
E) Damage: # of hitting missiles * (4D-Armour) [Single roll]

Even at long range a few missiles will hit.
Damage will be proportional to number of missiles fired, but Armour will not be irrelevant.
 
Ive also submitted a PD table to Matt. I've found formulas scare ppl off vs a simple table (totally my opinion/experience). I also allows for a rising/geometric scale of %ages

The only thing off with ur calculation is that PD can takeout multiple missiles. So you want the max at 500% or so
 
Nerhesi said:
The only thing off with ur calculation is that PD can takeout multiple missiles. So you want the max at 500% or so
I don't understand the 500%, you can't hit with more missiles than fired?

The % hit can easily be made into a table (if the formula is simple I don't ever have to look at the table, even better).
 
AnotherDilbert said:
Nerhesi said:
The only thing off with ur calculation is that PD can takeout multiple missiles. So you want the max at 500% or so
I don't understand the 500%, you can't hit with more missiles than fired?

The % hit can easily be made into a table (if the formula is simple I don't ever have to look at the table, even better).

Ah

You've done the inverse. In your solution, skill comes into play only for the launcher. So PD is no skill, just remove 1 missile per PD.

I've done the opposite. Because a skilled PD-Operator can take out 5 missiles. So launching all missiles ontarget is "no skill", but the roll determines how effective the PD is.

I figured to be in-line with Matt's recommendation, firing the missile isn't skillful, but shooting them down is :)
 
Nerhesi said:
So PD is no skill, just remove 1 missile per PD.
No, not really.

Example:
I fire 10 missiles.
...
I achieve an attack roll of 9, so 90% hit = 9 missiles.
the enemy has a laser turret with a skilled gunner, shooing down 5 missiles
so 4 missiles do damage
 
EW should require specialized gear rather than be lumped into standard ship sensors/software/etc. EW is like free point defense ('cause if you think about it, EW is really the blinding of sensors, and ships(players) have to use their sensors to get a firing solution, just as the missiles need them. Question is, do we want to make EW require dedicated equipment, dedicated software, and perhaps dedicated ECCM on the opposing ship to offset it - assuming you buy it? Might be betting too complicated here.

IF you wanted to complicate missiles a bit, you could make them either fire-and-forget, or command-controlled. Obviously the command controlled would have more luck as they can use a person AND a ships sensors to block EW attacks. Then again if you can jam the com link, you force the missile into standard FF mode. It would also mean having X number of missile command links available, much like the earlier missile cruisers required a separate targeting radar per missile. This may be better left along the wayside however.

Easiest way to handle it is to do it based on percentages - so that 10% of a 10missile salvo is treated the same as 10% of a 1,000 missile salvo. Since TL's aren't being put into the mix you want to keep it based on something that scales UP or down.

And your point defense should also be structured along similar lines. There's ALWAYS potential that you could get a leaker, or there should be, within reason. Say a single laser has a 50/50 chance of hitting a missile. Assigning TWO lasers to it means you have a guaranteed kill. But it means you can only engage half as many missiles as your have lasers for point defense (dedicated systems should have higher chances to kill as well as higher ROF, after all that's the only thing they are good for).
 
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