Making Sense of Astrogation

By FreeXenon, in Star Wars: Edge of the Empire RPG

edit 1: separated calc mods and difficulty upgrades into the basics and then added my personal tastes.
edit 2: changed last half of minimum difficulty table
edit 3: added more explanatory text to base difficulty
edit 4: added advantages/threat table, and spoiler block with image of astrogation rules
edit 5: added reconciled info from the Corellian Shuffle from Sons of Fortune

This thread split from my other thread: Galaxy Mapper and Setback Dice

OK, so I spent some the better part of this week with what is written in the book, and looking at Beyond the Rim to see how their astrogation checks were put together, and I think I have it down pretty good.

Reconciling the Known Astrogation Info - Core Book

The the key sentences in the Core Book in the astrogation skill and the astrogation section says the following:

  • under ideal conditions , this requires an Easy (*) check .
  • difficulty is based upon the area being targeted and the distance being traveled
  • travel to a nearby system along a well established route is generally an Easy (*) check
  • the difficulty increases based on the accuracy of navigational information and other factors.

Base Calculation Difficulty is based on initial accuracy of the maps and then minimums are set based on distance in the first two tables. These two tables basically reconciles all 4 base statements in the core book in setting the base difficulty based on maps and distance traveled.

The possible exception of the last one, which could mean general accuracy or where they are out-of-date or not. The basic mods given in the book say that as well, but this violates the internal consistency of the way base difficulty and setback die work. Difficulty Dice represent the base difficulty and setback die represent complications: ie - out of date maps. So, in my opinion the +1 difficulty rating due to maps being out of date, counterfeit, etc should be turned into setback dice to be internally consistent with game mechanics, and, fortunately, to give sbd for Galaxy Mapper (and other talents) to be useful. This is also reflected in the Beyond the Rim astrogation checks to which you will see in a moment.

Reconciling Beyond the Rim Astrogation Info

Below is listed the astrogation options from this adventure:

Option 1: Part I - jump from the Wheel which is located in the Besh Gordan system (mid rim) along the Perlemian Route which is listed as average (2 diff die) since this major hyperspace route is regularly updated. My tables show that this would start at 1 diff due to it being along a major hyperspace route with a minimum of 2 diff due to distance (within/between region) which results in a 2 difficulty.

Option 1: Part II - jump to the Cholgann from the end of the Perlemian Route is listed as hard (3 diff dice) with 2 sbd due to out of decades old out of date maps. This is where I set the baseline for my sbd calculation modifiers - 2 sbd for decades old maps, and this also shows that map accuracy should be handled by sbd. My tables set the difficulty at hard since they are in the outer rim with a min of 3 difficulty since this may be between sectors with 2 sbd for decades old maps.

Option 2: Direct Jump: The Cholganna system according to wikipedia and as referred to in the adventure puts it @ T-5 on the map in the book and off the beaten path at the end of the major Perlemian Hyperspace route. The Cholganna is not shown on the map in the book, but it is most likely there @ T-5 near the Drongar System. The book states that a route to this system is uncharted and is handed a 4 difficulty astrogation check. My tables below would also do as such - never mapped - difficulty 4. (This is also used to set the upper bound on the base difficulty)

Reconciling info from the Corellian Shuffle from Sons of Fortune

OK, this took me a little bit to figure out, but reading the whole modular encounter does help. This introduces the idea of microjumps and precision microjumps. This combined along with some stuff in Beyond the Rim (arriving @ a base of medium range), and it looks pretty good. Microjumps are wi/ system jumps and normally an issue and are 1 round easy (1 dd) astrogation check. For precision microjumps (arrive locations at a exact location in space),ups the difficulty, which results in the following being added to the charts:

1 rnd calc time for micro jumps

1 dd arrival wi/ short range
2 dd arrival wi/ close

1sbd (precision) use hyperdrive < class 5 else setback die


My New Astrogation Rules

Base Calculation Difficulty (how well originally mapped)
Choose most limiting: traveling from or traveling to
diff example
1 diff near major hyper routes; very well mapped (~core)
2 diff near minor hyper routes; moderately well mapped (~inner rim)
3 diff off the beaten path; slightly mapped (~outer rim)
4 diff unknown space; never mapped
Minimum Base Difficulty ( based on distance)
(see post below, I have edited the last half of table quite a bit)
min diff. calc time distance
1 diff 1 rnd within system
1 diff 1-4 rnds within sector
2 diff 5-8 rnds within/between regions
3 diff 9-14 rnds across 1 whole region+
4 diff 15-20 rnds across 3 whole regions+
5 diff 21-25 rnds across 5 whole regions+
Calculation Modifiers (how recently updated)
Choose most limiting: traveling from or traveling to time example
1 sbd a few months or yrs old
2 sbd a few decades old (< 50 yrs)
3 sbd 50-100 years
-- > 100 years consider unmapped)
For my personaly tastes I would change the last entry (>100 yrs) and add the following to show that such foolish things are dangerous:
1 upgr/2 sbd > century
2 upgr/1 sbd never mapped
All I had for this table was from Beyond the Rim's decades old at 2 sbd, and the rest is flavored to taste. In my opinion jumping into a system that has never been mapped or really out of date maps should be dangerous reflecting the upgrades to show as much. Now the Option 2 from Beyond the rim would have been 2 difficulty dice/2 challenge dice/1 sbd with this. So, for most this will be adjust to gaming tastes.
Astrogation Circumstantial Modifiers
+difficulty description
3 dd dmg/missing navicomp/astromech
1 dd quick/emergency calcs (-3 rnds)
1 dd ship slightly dmg'ed
1 dd arrival wi/ short range
2 dd arrival wi/ close
2 dd ship heavily dmg'ed
1 sbd (precision) use hyperdrive < class 5 else +1 sbd
Above is a more standard look and includes only the base table from the book. I would, however, split the first entry into 2 and then add some upgrades to show that such things are truly dangerous and should not be contemplated lightly.
1 upgr & 2 dd dmg/navicomp/astromech
3 upgr missing navicomp/astromech
I have gone back and forth on this one, but now that I have a more consistent system that follows the rules and examples FFG has shown us, I have come back to keeping the base modification dice, dropping the one about out of date maps, since it should not be there, and should be a sbd based modifier. I did convert the +3 dd from damaged/missing navicomp/astromech to upgrades/dd instead to reflect that performing that calculations by hand is really dangerous. Of course that will be flavor to taste too. Keeping it as is in the book should work just fine too.
Triumph and Despairs, etc
Calculations
1 success reduce calc time (-1 rnd per)
1 triumph compete calcs in min time; instant microjump
2 triumph calcs done now (stored calc)
1 threat increase calc time (+1 rnd per)
1 despair calcs done in max time +50%
2 despair calcs done in max time +200%
Travel (arrive at base of medium range)
1 success better location (-1 rng band per)
1 advantage reduce travel time or locate stop overs
1 triumph min travel time; new minor route; other new info/new planet/etc
2 triumph new major route; other new info/new planet/etc
1 threat worse location (+ 1 range band); ⇑ travel time
1 despair in light/med. asteroid/debris field; in grav. field/interdictor; near pirates/combat (med.);
2 despair in hvy asteroid/debris field; active battle ground (close); plot person setting a trap;
Equipment
2 threat minor navcomp/drive misalignment (1 setback die to astro checks) [mech or comp 5-10 min];
hyperspace turbulence - 2 ship strain
3 threat major navcomp/drive misalignment (2 setback die to astro checks) [mech or comp 20 - 30 min];
hyperspace turbulence - 4 ship strain
1 despair hyperdrive/navicomp minor break
2 despair hyperdrive/navicomp component critcal
Astrogation Rules on Wayfarer Action Sheet

Astrogation%20Rules%20from%20Action%20Sh

Edited by FreeXenon

Or we could just fold it into the Computer skill?

True! You could, although there currently is a skill for it.

In either case, you would still have to figure this stuff out in order to do it with either the astrogation or computer, right? =)

It has taken me a while to figure the basics out so that it jived with the rules and examples. Hopefully, some can benefit from the work I have done. =)

Yeah its probably the skill that has me scratching my head the most on how to use it.

You've got some goods ideas.

Edited by The Human Target

Thanks!

Yea, I spent the better part of this week trying to figure it out.

I hope you find it some use.

Right. I'll post my results here.

Granted, there were a few astrogation checks during the session and I got to test both your (previous) guidelines and my own adjusted version of that.

Long story short, both worked well. My current idea is this: you either the age of the data or the location/destination as base difficulty, and then have sbds added based on the one not used for difficulty dice. My initial idea is to use the lowest for difficulty; so if the data is recent, but the location is more difficult, you could use the recent data as base difficulty and add sbds from location, if its the other way around, your position generates a lower base difficulty, while the data age adds sbds.

So, for example: while in the core, or along a major hyperspace lane, using a few decades old data, that would be 1 diff + 2 sbds. On the other hand if the data is recent - like within a week or month, the base difficulty is 1, even if you're in the outer rim, but that would add 2-3 sbds. Based on the numbers both you and I have been using...

How this mess with Astrogation could get pass throughout the whole beta testing?

You are doing something nice here, I like most of it but the Astrogration difficulty upgrades, which seem they are a reminiscence from the table 7-13 from the core book. I don't find it elegant to add difficulty die. Following the philosophy of the game, I think that everything but the base difficulty shall be deal with set back die and / or difficulty upgrades.

One question, why did you stopped at daunting dif 4? Why did you not use the Formidable dif 5?

Cheers,

Yepes

I dig that you've added a bunch of conditions that warrant difficulty upgrade. More Despair = more splatter. Yes!

How this mess with Astrogation could get pass throughout the whole beta testing?

You are doing something nice here, I like most of it but the Astrogration difficulty upgrades, which seem they are a reminiscence from the table 7-13 from the core book. I don't find it elegant to add difficulty die. Following the philosophy of the game, I think that everything but the base difficulty shall be deal with set back die and / or difficulty upgrades.

One question, why did you stopped at daunting dif 4? Why did you not use the Formidable dif 5?

Cheers,

Yepes

Yea, the upgrades are more a personal choice. If I were to sterilize that out, I would have left it at the difficulty dice upgrades just like it was in the book.

Why I stopped at daunting, well I had not really thought about it until you just asked, but in Beyond the Rim, jumping into an unmapped location is 4 diff, which is also part of the reason I like the upgrades, to make it truly dangerous to jump into an unmapped location.

@Jegergryte - thanks for the update. I am glade to see some actual field testing of these ideas.

I am glad that they basically worked!!

@Yepesnopes, yea, I tend to agree with the adding difficulty dice thing, however, I tried to keep everything as consistent as possibly with what was originally in the book.

One question, why did you stopped at daunting dif 4? Why did you not use the Formidable dif 5?

Curse you and your question asking! =)

Ok, with that questions grinding my gears, I have modified the Min Base Diff chart as follows:

Minimum Base Difficulty ( based on distance)
min diff. calc time distance
1 diff 1 rnd within system
1 diff 1-4 rnds within sector
2 diff 5-8 rnds within between regions
3 diff 9-14 rnds across 1+ regions
4 diff 15-20 rnds across 3+ regions
5 diff 21-25 rnds across 5+ regions
Edited by FreeXenon

I realised that I don't understand how you want to calculate the difficulty:

Let's say I want to jump onto the hyperspace while in the Outerim (3 diff) but I am going to travel within the sector only (1 diff), which is the difficulty of the Astrogation check? 3 or 1?

Choose the one that is most limiting since you are going to have to travel through it.

3 dd - the distance table only sets the minimum difficulty.

So it would be Outer Rim (3 dd) with a minimum difficulty of 1. Since the 3 difficulty is greater than 1 you are golden.

You could have switched either table and get the same result.

Edited by FreeXenon

I like your take. Still, I'll probably be going for the least difficult setting the difficulty, and the most difficult setting number of setback dice, I like to be generous and less chance for muck up when it matters :)

Anyways, thanks for doing this, it's lead me to a solution I really like. Nice.

Awesome!

Glad to have been of help! =)

I will also likely use this in my games, when needed. I'll let you know how it turns out, should be next weekend!

I am running Trouble Brewing and Debts to Pay next weekend. I will use your chart and see.

With a quick look, the first thing that is changing is the Easy (1d) astrogation check in Trouble Brewing to get close to the asteroid field is going to be Hard (3d) with 1 upgrade...Although I will let them to skip the roll if they are with the Astromech droid.

Edited by Yepesnopes

I am running Trouble Brewing and Debts to Pay next weekend. I will use your chart and see.

With a quick look, the first thing that is changing is the Easy (1d) astrogation check in Trouble Brewing to get close to the asteroid field is going to be Hard (3d) with 1 upgrade...Although I will let them to skip the roll if they are with the Astromech droid.

Is that the one on pg 430 for Trouble Brewing? What I have laid forth does not really cover a situation like that. For me, using the astrogation for sensors does not make a lot of sense. Computers is what it should be. Their writing it that way is really confusing. I have sensor rules which would most likely put it at about 1 dd and possibly 1 sbd assuming that they are using active sensors.

Where is Debts to Pay from? Never mind! I found it.

Edited by FreeXenon

I added more explanatory text to base difficulty to make it more clear:

very well mapped

moderately well mapped

slightly mapped

@ Yepesnopes

The trip from Formos to the asteroid field is what you are talking about...

Yea, it could be 3 dd assuming that this is taking place in the outer rim. If it is near a hyperspace lane or happens to be well a traveled the difficulty could be less. I have not fully read the adventure

They do not specify a difficulty for the trip itself on the assumption that the droid will be there. The 1 dd on 430 is for scanning the asteroid and not for the hyperspace route, as far as I can tell. :D

How does a person put a spoiler box in their post?

[ spoiler ] :D

Every time I try to do this I keep thinking [ sblock ] and that is not it.

Ta!

If you may be interested here is the chart of advantages/threat/etc that I have come up with:

Calculations
1 success reduce calc time (-1 rnd per)
1 triumph compete calcs in min time; instant microjump
2 triumph calcs done now (stored calc)
1 threat increase calc time (+1 rnd per)
1 despair calcs done in max time +50%
2 despair calcs done in max time +200%
Travel (arrive at base of medium range)
1 success better location (-1 rng band per)
1 advantage reduce travel time or locate stop overs
1 triumph min travel time; new minor route; other new info/new planet/etc
2 triumph new major route; other new info/new planet/etc
1 threat worse location (+ 1 range band); ⇑ travel time
1 despair in light/med. asteroid/debris field; in grav. field/interdictor; near pirates/combat (med.);
2 despair in hvy asteroid/debris field; active battle ground (close); plot person setting a trap;
Equipment
2 threat minor navcomp/drive misalignment (1 setback die to astro checks) [mech or comp 5-10 min];
hyperspace turbulence - 2 ship strain
3 threat major navcomp/drive misalignment (2 setback die to astro checks) [mech or comp 20 - 30 min];
hyperspace turbulence - 4 ship strain
1 despair hyperdrive/navicomp minor break
2 despair hyperdrive/navicomp component critcal
I will also post this in my OP too.
Any thoughts on these?

I have reconciled and added the astrogation info from the Corellian Shuffle from Sons of Fortune

OK, this took me a little bit to figure out, but reading the whole modular encounter does help. This introduces the idea of microjumps and precision microjumps. This combined along with some stuff in Beyond the Rim (arriving @ a base of medium range), and it looks pretty good.

Microjumps are wi/ system jumps and normally an issue and are 1 round easy (1 dd) astrogation check. For precision microjumps (arrive locations at a exact location in space),ups the difficulty, which results in the following being added to the charts:

1 rnd calc time for micro jumps

1 dd arrival wi/ short range
2 dd arrival wi/ close
1 sbd (precision) use hyperdrive < class 5 else setback die
My only question to you all is:
Is there any support for slower hyperdrives being more accurate? This is the part of it that bothers me.
edit: sentences were really bad
Edited by FreeXenon