I'm currently trying to write an encounter where the PCs have to sneak past an Imperial blockade using a planetary ring system for cover, but the rules don't really seem to suggest any interesting way of handling this. The existing rules for sensors are a bit vague and minimal:

• You passively detect all ships within sensor range.
• You can make an Easy computers check to focus active sensors out one range band further in one arc.
• You can make a Perception check to scan the enemy in combat.

What I want are sensor rules that enable the following bits of gameplay:

• Sneaking past blockades that use passive sensors should be possible.
• Evading active sensors should be possible.
• 'Going dark' should be a thing.
• Using stellar phenomena to hide should be a thing.
• There should be some degree of tension/cat-and-mouse.

I've not found any existing homebrew to cover this, but there's some existing bits of core rules that might be applicable:

• The speed/silhouette difficulty mechanics for difficult terrain.
• The silhouette difference difficulty modifications from starship combat attacks.
• The range band difficulties from combat.
• Adding terrain rating in Boosts to Stealth/Perception checks (or equivalent).
• Adding terrain rating in Setbacks to Piloting checks.

So I've been thinking of possible rules to handle these encounters:

• A ship can 'go dark'. This disables shields and weapons, but means that it requires an opposed Perception vs Computers check for ships to detect you when you are in sensor range.
  • Add Setback dice equal to the difficult terrain rating.
  • Add Boost dice equal to the ship's speed.
  • Modify the difficulty according to the silhouette difference modifiers.
  • If successful, the searching ship knows something is out there at a given arc and distance, and can switch to Active sensors.
• Focusing active sensors on a contact requires an opposed Perception vs Piloting check
  • Modify the difficulty as above, but also add Setback dice equal to the difficult terrain rating.
  • If successful, the searching ship knows the location of the targeted ship and it no longer benefits from 'going dark'.
• As an action, assuming they don't enable shields or weapons, a detected pilot can attempt an opposed Piloting vs Vigilance check to evade again.
  • Add Boost & Setback dice equal to the difficult terrain rating.
  • Add Setback dice equal to the ship's speed.
  • Modify the difficulty according to the silhouette difference modifiers.
  • If successful, they evade the active sensor sweep and end up in a different arc.
  • This should add some cat & mouse gameplay, as the stat/skill to detect is different from the stat/skill to keep a target detected.
• For each time a ship has successfully evaded its pursuers, downgrade the difficulty of all future Perception checks once and the difficulty of all future Piloting checks once.

Does this seem reasonable? My thoughts are:

• I really wanted to include the speed/silhouette difficulty mechanics, but what we want is the opposite , i.e. that smaller/slower ships should be easier. We could reverse it and have the speed/silhouette be the detector's dice pool, but then this leaves no real space for the skills or abilities of the character performing the test.
• Is Computers is the right skill for handling how effectively a ship has 'gone dark'? Stealth or Piloting would be a bit inappropriate as this doesn't seem like an Agility roll . Alternatives would be something like Skulduggery , Vigilance or Cool ? Cool seems like a possible good fit as it's a very 'smuggler' skill, but has a fairly weak connection to what's going on (you could argue 'keeping your nerve' is the challenge?).
• The double-counting of difficult terrain in some checks seems odd. It simultaneously makes it easier to hide, but also harder to pilot as per the regular piloting rules. Having them cancel out would be simpler, but would remove the benefit of talents that let you remove Setback dice from terrain.
• Things escalate so you can't just keep dodging over and over- eventually it becomes impossible to keep hiding.
• Other than that, this is relatively simple, which seems like a good idea, but some System Strain could probably be added somehow.

If they're not bad I'll try and write them up in a neat format with examples of use.

46 minutes ago, Talkie Toaster said:

What I want are sensor rules that enable the following bits of gameplay:

• Sneaking past blockades that use passive sensors should be possible.
• Evading active sensors should be possible.
• 'Going dark' should be a thing.
• Using stellar phenomena to hide should be a thing.
• There should be some degree of tension/cat-and-mouse.

There is no reason these can't be a thing. just because they aren't spelled out for you doesn't mean they aren't applicable. Remember the devs of these rules tried to just give you broad rulesets that you can then adapt as needed. They didn't WANT to go super detailed with the stuff. All of those things can be easily factored just by adding setback dice, or upgrading the scanning check of the opposing party.

So to go over your points one by one:

1. Sneaking past blockades that use passive sensors should be possible. 'Going dark' should be a thing. (These 2 feel part of the same thing)

Sure, but the party would need to make some effort for it. They would need to "go dark" as you mention, to have a good chance of pulling it off. Shutting down systems, trying to aim the ship ahead of time in a direction that would let them move past in a purely ballistic way. I see no reason why this isn't possible. In fact didn't Han and Chewie do that very thing in Empire when they were running from the Imperial fleet? I seem to recall in at least one scene, if not 2, they specifically make a point to hide somewhere, and then shut off all the systems, to try and vanish from sensors. And I would be shocked if this tactic didn't come up in one of the tv shows, like Clone Wars, or Rebels, I didn't watch them till the end so I can't remember. But I seem to recall this tactic used on a few occasions.

2. Evading active sensors should be possible.

Again, no reason this shouldn't be possible, as we see examples of it in the franchise. But it's more difficult, as it's an ACTIVE scan. They are making a specific effort to look for anything out of the ordinary. So without any attempts by the ship to alter their appearance from their ship silhouette, or something else to hide, the likelihood is very low. It's the space equivalent of someone standing out in the middle of a flat, open field, and wondering why the lookouts posted at a watchtower can see them. They kind of don't have any way to hide, at least not without a lot of effort. Now a good GM should always account for things for the party to use to their advantage, similar to the "there should always be some cover objects close by for the PCs to duck behind, fights don't happen in featureless, empty rooms very often." There is no reason something similar couldn't be said for space scenes. If it's a heavily trafficked area, they could try and use other ships as cover to hide behind during an active scan. They could maybe find a nearby comet that passes through the zone, and use it's tail as cover to make an approach. Any number of things. As the GM, it's your job to think up a handful of things they could utilize in the environment, to accomplish this very thing. It's still a contested check, so it's not a guarantee of hiding, but it gives them a chance.

3. Using stellar phenomena to hide should be a thing.

It is a thing, by virtue of you saying it should be, it now is. Just implement it. Again, the franchise gives us plenty of examples of it, so it's hardly without precedent in the SW-verse.

4. There should be some degree of tension/cat-and-mouse.

Yes there should, but is that really something that needs a specific mechanic to accomplish?

1 hour ago, Talkie Toaster said:

Is Computers is the right skill for handling how effectively a ship has 'gone dark'? Stealth or Piloting would be a bit inappropriate as this doesn't seem like an Agility roll . Alternatives would be something like Skulduggery , Vigilance or Cool ? Cool seems like a possible good fit as it's a very 'smuggler' skill, but has a fairly weak connection to what's going on (you could argue 'keeping your nerve' is the challenge?)

Mechanics might also be viable...

Yeah, tough call, the whole point is not to merely shut down everything, but to shut down everything that generates some kind of detectable radiation... So it kinda feels like this should be a check that determines something like "You do it but...." where Advantage/Threat determine duration or System Strain inflicted or something...

I don't think these make sense in-universe. I must admit I didn't read them thoroughly, but that is because they are quite long and I believe the premise is flawed.

In-universe, "going dark" is basically shutting off all of your systems (even the droids) so they can't scan you. I'd say that works fine unless you are in motion, which would require a Vigilance check to realize that it isn't just a space rock. Precedent in Rebels, except for the motion part.

The scanner pick up everything within a certain radius, so you can't just fly past without getting noticed. To evade sensors, you need something like: 1. a Sensor Baffler (62 FO) upgrades the difficulty to detect the ship by 2. You could add that it can only be detected through the use of active sensors, though that might be a little OP. 2. a Pseudo-Cloaking Device (66 SM) which increases the difficulty to detect the ship by 2. Again, you could add that it can only be detected through the use of active sensors, though that might be a little OP. When used in concert with the Sensor Baffler, it results in the addition of 2 Challenge dice. 3. Electronic Counter-Measures. This one is a mixed bag. While it blocks sensors, it alerts ships to its presence as they realize that their scanners don't work.

14 minutes ago, KungFuFerret said:

[snip]

I don't quite get the point of this post. You agree with me that all my design goals are sensible, Star Wars-y things to want, so can you give an example of how you would GM them in the existing rules? I 100% appreciate that not everything has to be written out in full! But also, it's useful to have examples of how you could run a given style of encounter.

1 minute ago, P-47 Thunderbolt said:

The scanner pick up everything within a certain radius, so you can't just fly past without getting noticed. To evade sensors, you need something like: 1. a Sensor Baffler (62 FO) upgrades the difficulty to detect the ship by 2. You could add that it can only be detected through the use of active sensors, though that might be a little OP. 2. a Pseudo-Cloaking Device (66 SM) which increases the difficulty to detect the ship by 2. Again, you could add that it can only be detected through the use of active sensors, though that might be a little OP. When used in concert with the Sensor Baffler, it results in the addition of 2 Challenge dice. 3. Electronic Counter-Measures. This one is a mixed bag. While it blocks sensors, it alerts ships to its presence as they realize that their scanners don't work.

I think my problem here is that... there is, RAW, no check to detect a ship for all of these upgrades to modify- unless you're running one of the existing stealth ships. So when is it appropriate to make a check, and what should it be?

3 minutes ago, Ghostofman said:

Mechanics might also be viable...

Yeah, tough call, the whole point is not to merely shut down everything, but to shut down everything that generates some kind of detectable radiation... So it kinda feels like this should be a check that determines something like "You do it but...." where Advantage/Threat determine duration or System Strain inflicted or something...

I think either Computer or Mechanics could do it, as the controls for the ship systems are in the cockpit, that's the whole point of the control panels there. So I see no reason someone couldn't just flip all the needed switches to turn off and go dark. Mechanics would be a perfectly fine way to do it to, so to me, they are equally viable ways, depending on how the person tries to do it. If they are in the cockpit, I'd probably say Computers, to reflect them knowing which buttons to press, in what order, to safely power down. If they are say, in the engine room, mechanics would probably be more fitting, sort of like that scene in Firefly, when Kailey runs in there and starts pulling levers to power down.

I think the biggest issue is how quickly the person tries to do it, and whether or not the systems are powered down safely. If they are trying to go dark in a single round, I'd say that would be the "difficult" part of the check, reflected by setback die being added. I don't think the act of powering down is all that hard. I've worked jobs with massive machines the size of buildings before, and the process to shut them down usually isn't complicated, it's just knowing which to press in what order. The problems pop up when you are trying to do things fast, as the systems aren't necessarily designed to spin down that quick. So the "emergency" shutdown, can cause some serious backlash problems in the mechanisms, if you are not careful with what you do. This would show up as system strain or damage in my mind, considering what i've see happen when our equipment was shut down emergency style.

3 minutes ago, Talkie Toaster said:

I think my problem here is that... there is, RAW, no check to detect a ship for all of these upgrades to modify- unless you're running one of the existing stealth ships. So when is it appropriate to make a check, and what should it be?

That's why I said that maybe those attachments mean that the ship can't be detected with passive sensors.

Other than that, it's just active sensors.

10 minutes ago, KungFuFerret said:

I think either Computer or Mechanics could do it, as the controls for the ship systems are in the cockpit, that's the whole point of the control panels there. So I see no reason someone couldn't just flip all the needed switches to turn off and go dark. Mechanics would be a perfectly fine way to do it to, so to me, they are equally viable ways, depending on how the person tries to do it. If they are in the cockpit, I'd probably say Computers, to reflect them knowing which buttons to press, in what order, to safely power down. If they are say, in the engine room, mechanics would probably be more fitting, sort of like that scene in Firefly, when Kailey runs in there and starts pulling levers to power down.

I think the biggest issue is how quickly the person tries to do it, and whether or not the systems are powered down safely. If they are trying to go dark in a single round, I'd say that would be the "difficult" part of the check, reflected by setback die being added. I don't think the act of powering down is all that hard. I've worked jobs with massive machines the size of buildings before, and the process to shut them down usually isn't complicated, it's just knowing which to press in what order. The problems pop up when you are trying to do things fast, as the systems aren't necessarily designed to spin down that quick. So the "emergency" shutdown, can cause some serious backlash problems in the mechanisms, if you are not careful with what you do. This would show up as system strain or damage in my mind, considering what i've see happen when our equipment was shut down emergency style.

Since Star Wars hasn't really done this as far as I can recall you can go either way and be correct.

I just feel mechanics sounds good since it doesn't just show you shutting stuff down, but also shutting things down that probably weren't really meant to be shut down.

You make a good point about time though as going silent in premeditated way should be easier than just up and doing it. Feels like a good conditions table might be in there... Boost to plan ahead, Upgrade Difficulty when just up and doing it...

23 minutes ago, Ghostofman said:

Since Star Wars hasn't really done this as far as I can recall you can go either way and be correct.

I just feel mechanics sounds good since it doesn't just show you shutting stuff down, but also shutting things down that probably weren't really meant to be shut down.

You make a good point about time though as going silent in premeditated way should be easier than just up and doing it. Feels like a good conditions table might be in there... Boost to plan ahead, Upgrade Difficulty when just up and doing it...

Yeah my take on it would be, if the party tries to go dark early, outside of sensor range, then I wouldn't really bother with them doing any checks. It's not rushed, and should be easy for people familiar with the systems. BUT, the challenge would then be "how good is your Piloting aim skills, to make sure we fly on course well enough to not smash into anything, or be forced to power up and make a course correction, thus blowing our ballistic stealth trick." That would then change the skill check, at my table anyway, to a Piloting. Can Discount Han aim his thrusters and trajectory, well outside the system, and account for stellar drift and orbital mechanics well enough, to just drift in like a cold rock, from 2 hours outside sensor range? And still make it passed the blockade and onto the other side of the planet? Let's find out, roll the dice. If it's a "oh crap, Boochie kill the systems! go dark!" *frantic running around to do it in mere seconds* yeah that would be mechanics or computers, at my table anyway.

4 hours ago, Talkie Toaster said:

What I want are sensor rules that enable the following bits of gameplay:

• Sneaking past blockades that use passive sensors should be possible.
• Evading active sensors should be possible.
• 'Going dark' should be a thing.
• Using stellar phenomena to hide should be a thing.
• There should be some degree of tension/cat-and-mouse.

When I was preparing my game three years ago, I stumbled across this thread and made these house rules:

• Star systems are zone-divided into orbit rings, etc. for chase gameplay
• Scanners reveal degrees of information influenced by distance and number of Success
  • Number of scanner contacts
  • Size and movement
  • Type and armament
  • Tactical opportunities, cargo or other insights
• Base difficulty is Average, and closer ranges add 1 Success

This is intended to be used by player characters, and it's weighted for results (vague pings at the far end of a system are more fun, IME, than nothing) but could be modified to allow easier signal loss, especially using stellar phenomena. I discarded sensor ranges, as they don't add the tactical depth FFG had likely hoped for. Associated skill is Astrogation for sheer preference.

Some rambling thoughts:

p227 of EotE mentions Active scanning as an Easy check, one range band longer than the ship is rated for. I would have to think this assumes "clear space", with little terrain or other confusing objects. Personally I allow increasing difficulty to extend the range band, but YMMV. I also reduce the base range of every ship to Medium if it's listed as more. But Short would probably work too.

Terrain should play into it, using the chart on page 240, such terrain should add setback to a scan check.

Per RAW, the Star Destroyer can technically scan you before you can scan it, which is practically the opposite of every scene in the media. Anything Silhouette 6 or higher is almost always a big red flag for our heroes. I'd alter this, so if a baseline of Silhouette 5 is "neutral", then each Silhouette (or Sil/2 if you want to be conservative) above this decreases scan difficulty (to a minimum of Easy), while each Silhouette below this increases difficulty. This means Star Destroyers can be detected even at Extreme range by just about anybody (if using the modified rules above), which makes sense to me.

Active mobile objects exhibiting an energy signature reduce difficulty by 1 to a minimum of Simple. Multiple objects (eg: several Y-Wings approaching from different directions) should also reduce difficulty by 1. Floating passively with all energy sources powered down increase difficulty: by 1 if "floating through" a zone; by 2 if "floating with" a zone. Making sure everything is powered down should be a Leadership roll, or Mechanics/Computers if it's a one-man show.

A Pilot should be able to "float through" a scanned zone, even powered down, using directional jets. The difficulty of this should be based on terrain. Basic success means they get the benefits of getting closer to their goal, while also receiving the benefits of looking as if they're "floating with" the zone. Failure means they do not get closer to their goal. Threat might remove the "floating with" bonus, or cause system strain or even a collision. But a collision doesn't necessarily cause an alert (a debris field would be full of constant collisions).

Scanning is a Computers check (per F&D...EotE lists it as Surveillance, but there is no such skill). Scanners can be fooled or jammed. If you use the existing rules (EotE p237), the text doesn't apply to scanners, only comms equipment, so I'd alter it as follows: Jamming is an Average Computers check. Success increases the base scanning difficulty by 1, with each 2S above that increasing it again. I'd allow 1A to be spent affecting the scanner of another ship, and 2A to apply setback to all affected scanners. Threat/Despair can allow an unsuccessful scanner to realize they are being jammed, even if their scanning fails.

As for running the scenario, it sounds like it's basically a "get from A to B" challenge. Set a baseline of how many successful "movements" the party needs to get through the gauntlet ... I wouldn't set this higher than 2 or 3, since you probably don't want it to drag out but need to account for failure. The risks are system strain, collision, component failure, and detection, which should provide enough variety to make it a tense situation.

Look for emperor nortons starship rules he has so l.j e good sensor rules

Signals Intel

2 hours ago, Sturn said:

Signals Intel

^^ This.

We've been using them for quite some time and haven't looked back.

So Sturn, any chance to revisit these? New gear, hardware and attachments have come out since your last update. 🤩

5 hours ago, Sturn said:

Signals Intel

Wow, these are great! How did I miss them?

3 hours ago, whafrog said:

Wow, these are great! How did I miss them?

Well it's been a while since I've been here discussing anything. The entire set* is available here in the Star Wars tab > Vehicle Ops.

*Well, not entire. I've always had hopes of someday adding a mercantile document.

6 hours ago, Jareth Valar said:

^^ This.

We've been using them for quite some time and haven't looked back.

So Sturn, any chance to revisit these? New gear, hardware and attachments have come out since your last update. 🤩

Someday perhaps. But, currently my impetus to get back to FFG is a Genesys fantasy campaign with my daughter. So, that's where most of my game document creation time has gone. I've only recently noticed the Genesys Foundry, so I'm thinking of trying to tackle all the notes I've made for a home-brew world, home-brew rules, into a proper format for a Foundry entry?