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January 24th, 2008, 03:35 PM


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Autofire Issues in v3.2
A question and an observation:
Q1. How do "to hit" modifiers apply to autofire attacks, if they apply at all. (It would be helpful for the example to include the effects of the firer's Rifle skill).
Observation. This mechanic looks like it's defective. I can't tell for sure until the question above is answered.
To hit, you roll dice equal to the autofire rating of the weapon (usually 3 or 4). The lowest die is automatically the timing die. The remaining dice are individually paired with the timing die to produce several “to hit” rolls.
Here’s the example from the rules:
Morn fires his Advanced Combat Rifle (Automatic 4). He rolls four d6, and gets a 2, a 3, a 4, and a 5. The 2 is the lowest die, so it becomes the Timing die for the weapon. The other dice are Effect dice. Morn assembles three attacks 2+3=5, 2+4=6, and 2+5=7.
The problem is that there is a 52% chance of rolling at least one “1” on 4d6. And you cannot roll an 8+ if one of your dice is a 1! So poor Morn has a 52% chance of missing all three shots, just by rolling a 1 if he has no bonuses to the roll. Worse, if he fails to roll at least one "1", he has a 52% chance of rolling at least one "2", which is nearly as bad. If one die is a two, the other die *has* to be a "6" to score a hit.
When time permits, I'll run the statistics out. But right now, it looks like Morn has a better chance of hitting his target by firing 1 bullet rather than 12 bullets. And his chance of a miss *increases* as he fires more rounds...
Sigh...

January 24th, 2008, 03:44 PM


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I should add that *if* modifiers are added to the effect dice, then it will be nearly impossible to hit with autofire if there's a net negative modifier. A 1 modifier will make it impossible to score a hit if the timing die is a 1 or 2. There's an 81% chance of rolling at least one "1" or "2" on 4d6. So poor Morn will miss at least 81% of the time in that case.

January 24th, 2008, 08:32 PM


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There are no special modifier rules in the Autofire section. Therefore, it's reasonable to assume that modifiers apply to autofire "to hit" rolls like any other "to hit" roll.
If that is the case, it is virtually impossible to hit anything if there is even a 1 to hit modifier.
If a 1 or 2 is rolled, the to hit number cannot be 9+. And on 4d6, there's less than a 3% chance that a 1 or 2 won't be rolled.
I created a Monte Carlo simulation to roll 10K attacks at a time, assuming this is how it works. Here's the result:
2 on the "to hit" roll, <0.1% chance of scoring a hit. Average number of hits is 0.002. Compared with 16.7% chance of hitting with a single shot.
1 on the "to hit" roll, 5% chance of scoring a hit. Average number of hits is 0.09. Compared with 27.8% chance of hitting with a single shot; average hits 0.278.
No modifier on the "to hit" roll, 33% chance of scoring a hit. Average number of hits is 0.6. Compared with a 41.7% chance of hitting with a single shot; average hits 0.417.
+1 modifier on the "to hit" roll, 85% chance of scoring a hit. Average number of hits is 1.7. Compared with 58.3% chance of hitting with a single shot; average hits 0.583.
+2 on the "to hit" roll, 99% chance of scoring a hit. Average number of hits is 2.5. Compared with 72.2% chance of hitting with a single shot; average hits 0.722.
+3 on the "to hit" roll, 99.999% chance of scoring a hit. Average number of hits is 2.999. Compared with 83.3% chance of hitting with a single shot; average hits 0.833.
So...
1. Lousy shooters are far better off using single shots than autofire. Good shooters are far better off using autofire. (The exact opposite of what seems to be happening in the Real World; highly trained Allied troops in Iraq tend to use single shots, while poorly trained terrorists use autofire).
2. A mere +1 modifier can lead to a 6X increase in the chance of hitting. A +1 net modifier will result in a hit almost always, while a 1 net modifier will result in a miss 95% of the time. And a 2 net modifier makes a hit *impossible*.
3. The more bullets you fire, the less likely you are to hit in cases where there's no modifier or a negative modifier. With no modifier, an autofire of 3 will hit 37.8% of the time. With a 1, you'll hit 9.6% of the time (vs. 5% of the time with Autofire 4).
Is this really a good way to handle autofire?

January 24th, 2008, 08:51 PM


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Quote:
Originally Posted by tbeard1999
And you cannot roll an 8+ if one of your dice is a 1!

I haven't been keeping up with the play test because Mongoose already lost me. I think CT is better.
But, as to your comment above...
Unless they've changed it in v3.2, the shooter will have a +1 DM from skill (at Skill1), allowing for an 8+ throw if a "6" is thrown. 1 + 1 + 6 = 8.
Other modifiers (range) may apply as well.
If old Morn doesn't have a Skill1, then Skill0 avoids the penalty (and, you're right, the Skill0 character cannot hit unless modifiers for range help him).
Those that aren't skilled use a 3 DM, IIRC.

January 24th, 2008, 08:55 PM


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Quote:
Originally Posted by tbeard1999
Is this really a good way to handle autofire?

You are being too negative.
Think of it as encouraging moderation and punishing people who want to machine gun everyone they meet.

January 24th, 2008, 10:01 PM


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Quote:
Originally Posted by atpollard
You are being too negative.
Think of it as encouraging moderation and punishing people who want to machine gun everyone they meet.

Well you are definitely "a glass half full" kinda guy. Or in this case, a "glass 1/64th full" kinda guy.

January 25th, 2008, 08:01 AM

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With all this talk of percentages describing probabilities to hit, etc. (very logical, intuitive and interesting it is by the way), why doesn't someone design an RPG based on percentile probabilities upwards? Oh...hang on, they have already! It's called Basic Role Playing (BRP)
http://basicroleplaying.com/
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January 25th, 2008, 09:28 AM


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Quote:
Originally Posted by tbeard1999
Well you are definitely "a glass half full" kinda guy. Or in this case, a "glass 1/64th full" kinda guy.

On a more serious note:
As you pointed out, the probability of rolling a (1) approaches 100% as the number of dice increases. For the sake of argument, let us accept that a timing of (1) in unavoidable in certain situations.
If the available modifiers (range, skill, whatever) yield a positive value that allows a roll of (6) on the other dice to hit, then it is POSSIBLE to hit the target. If a timing roll of 1 is unavoidable and an ‘effect’ roll of 6 is required to hit, then there is no penalty to additional dice and very high cyclic rates are only beneficial. Under such a system, a 10 round autofire burst is better than a 4 round burst (9 chances to roll a 6 instead of 3). A 100 round burst would be even better (16+ rolls of 6 on average) and a 1000 round burst would be the best (166+ rolls of 6 on average).
Would anyone like to ‘spray and pray’ with a VRF ‘Gattling’ pulse laser ?
Perhaps some sort of (house?) rule that an effect roll of 6 always ‘hits’ [but forfeits the super damage] to avoid ‘impossible’ shot situations  [My character charges the machine gun because my armor and evasion bonus mean that the autofire cannot hit me].

January 25th, 2008, 11:39 AM


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Quote:
Originally Posted by atpollard
On a more serious note:
Perhaps some sort of (house?) rule that an effect roll of 6 always ‘hits’

<swears under breath; kicks trash can across the office>
This is the real problem. It seems like every specific use of the timing/effect system winds up needing special house rules.
And the number of special rules necessary to beat even vaguely reasonable results out the mechanic is going to exceed the MGT rules in length. And, as an added "bonus", a poorly conceived, poorly tested, fiddly, nonintuive mechanic will become exceptionriddled as well. Oh boy.
The result is wheeeeeeeeeee, another crappy version of Traveller. And boy, doesn't Traveller need yet another crappy version? I was just saying yesterday how we didn't have enough Traveller versions with obtuse, defective, illogical and absurd mechanics...
At some point, a clearly defective mechanic just needs to be replaced. In my opinion, this one should never have even made it to general playtest. While I've come up with mechanics as bad (or worse), I have never let them see the light of day.
I sure hope MWM got his money up front from Mongoose.

January 25th, 2008, 12:04 PM


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Quote:
Originally Posted by tbeard1999
<swears under breath; kicks trash can across the office>

Breathe. In through the Nose and out through the Mouth. Again  Deep  Slow. Feel better?
I prefer a straight Roll 2D6, 8+ to hit, myself (and that is supposed to be an option). The issue of cannot miss/cannot hit situations is part of every game mechanic. Either you accept it, or you create some version of the "1 always fails and 20 always succeeds" rule. I prefer to always allow some chance, but that is just my preference.
Is it really such a 'game killer' if an unskilled character spraying the room with bullets has so little control over the weapon that he cannot hit his target? He could fire a weapon with shorter bursts or get more skill before attempting that task. It affects 'in game' decisions, but has it really proven unworkable? What about all of the other possible combinations that result in an automatic failure or success  do you feel this strongly about them?
Last edited by atpollard; January 25th, 2008 at 12:08 PM..

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