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Ash DuQuennes
14 March 2002, 07:29 PM
Here are some expanded rules I've used for Star Wars D6. Basically, my players wanted to be sneaky on occasion, and "slip" past Imperial Blockades, Patrols, etc. Since they do it in some of the various novels, we figured players should be able to do it "in game." So I sat down, racked my brain, remembered some of my Tom Clancy, and came up with some expanded rules for Sensors. With these, my players actually put CPs into their Sensor skill!

Sensors.

I've multiplied all Sensor ranges by 10, as the given ranges were so short that quite a few ships could cross their own Sensor "footprint" in one combat round. This is the equivalent of running through a dark building with a weak flashlight pointed just in front of your feet (maybe not that bad, but it wasn't all that great, either).

Additionally, a ship's Sensor emanations can be detected, or "intercepted," by another ship at certain ranges beyond which the Sensing ship can get a "return" due to the weakening/degradationof the Sensor signal as it propogates. The closest analogy would be that, at night, if you had a flashlight, people could see you from further away than your flashlight beam would illuminate.

Naturally, Sensors in Passive mode have no emanations to detect.

In Scan Mode, the Sensor signals propogate 3 dimensionally all around the Sensing vessel. The difficulty to intercept Scan Mode emanations is as follows:

Intercepting Vessel is less than x1 Scan Mode Range: Very Easy.
Intercepting Vessel at or above X1 and less than x2 Scan Mode Range: Easy.
Intercepting Vessel at or above X2 and less than x3 Scan Mode Range: Moderate.
Intercepting Vessel at or above x3 and less than x4 Scan Mode Range: Difficult.
Intercepting Vessel at or above x4 and less than x5 Scan Mode Range: Very Difficult.
Intercepting Vessel at or above x5 Scan Mode Range: Heroic.

In Search Mode, the Sensor signals propogate from the detecting vessel outward in a 90* cone into one of the four firing arcs. For it's sensor emanations to be intercepted, the intercepting vessel must be either in the Search arc, or in one of the two adjacent arcs.

Intercepting Vessel is less than x2 Search Mode Range: Very Easy.
Intercepting Vessel at or above X2 and less than x4 Search Mode Range: Easy.
Intercepting Vessel at or above X4 and less than x6 Search Mode Range: Moderate.
Intercepting Vessel at or above x6 and less than x8 Search Mode Range: Difficult.
Intercepting Vessel at or above x8 and less than x10 Search Mode Range: Very Difficult.
Intercepting Vessel at or above x10 Search Mode Range: Heroic.

For vessels in the arcs adjacent to the arc being Searched, double the difficulty.

In Focus Mode, the Sensor emanations propogate from the detecting vessel in a very tight arc into one of the four firing arcs. This creates a very narrow cone. Because of the power being channeled into Focus Mode, they are very easy to detect.

Intercepting Vessel is less than x4 Focus Mode Range: Automatic (as long as someone is looking; see below).
Intercepting Vessel at or above X4 and less than x8 Focus Mode Range: Very Easy.
Intercepting Vessel at or above X8 and less than x12 Focus Mode Range: Easy.
Intercepting Vessel at or above x12 and less than x16 Focus Mode Range: Moderate.
Intercepting Vessel at or above x16 and less than x20 Focus Mode Range: Difficult.
Intercepting Vessel at or above x20 and less than x25 Focus Mode Range: Very Difficult.
Intercepting vessel at or above x25 Focus Mode Range: Heroic.

If the intercepting vessel is outside of the Focus Arc, but still within the same general firing arc, the sensor emanation may still be intercepted because of its high power. Add +5 to the target number in those situations.

A player must announce that they are either attempting to detect Sensor emanations, or that they have configured their sensors to alert them somehow when a sensor emanation is detected. This could be very annoying in crowded space, but for a scout/recon ship trying to sneak up on a secret, out-of-the-way Imperial Base....

The player then announces whether they are doing a Passive or Directed Intercept.

A Passive Intercept means that they are able to receive signals from any direction, and they get to add their own ship's Scan Mode DM to the attempt.

A Directed Intercept works two ways: Broad Directed and Narrow Directed.

Broad Directed Intercepts search in a 90* cone in one of the four firing arcs, and allows the operator to add to Search Mode DM to his Sensor Roll to intercept sensor emanations.
Narrow Directed Intercepts search in a narrow arc equivalent to their Focus Mode, and allows the operator to add the Focus Mode DM to his Sensor Roll to intercept sensor emantions.

Sensor Masks.

These very expensive devices (150,000 Cr per Hull Die for Starfighter Scale, 300,000 Cr per Hull Die for Capital Scale, and that's before Black Market Inflation kicks in!) add 2D to the difficulty to be detected or identified. Simlply add the opposition's Sensor skill and Sensor Mode DM together, then subtract 2 die. That's the basic rule. I've added a twist. They operate in either Automatic or Manual Modes.

In Automatic Mode, the device works on its own programming, and performs as described above.

In Manual Mode, the Sensor Mask operator (skill: Sensors) gets to add his/her Sensor skill dice into the equation.

A Mean Twist To Make Your Players Really, Really Hate You.

In most games, your players will be in a Starfighter-scale vessel (such as a light freighter). Well, here's your chance to really screw them: use the Die Cap System, from 2ed. (not 2ed., Revisd and Expanded!).

I'll illustrate with a scenario: your players are a Special Ops. Team for the Alliance, trying to sneak onto a planet under blockade by several Star Destroyers. Since "punching through" might be akin to suicide (and blow the mission cover), they decide to "sneak" through, using Sensor Intercepts to try to find blind spots in the Star Destroyer's sensor coverage.

Star Destroyers are big, powerful, top-of-the-line military technology. Your player's freighter may be hotter than the Millenium Falcon, but it has only a fraction of the power and computer capacity available to it as the Star Destroyer does. So when they are rolling to determine whether they are intercepting Imperial Star Destroyer sensor emanations, give them the Die Cap of 3 (4, 5 and 6 are converted to 3).

Same with the Sensor Mask.

If they should happen to have a Sensor Jammer, and try to use it to prevent detection and/or identification against a Capital-scale vessel (or just a Capital-scale military vessel), again, hit 'em with the Die Cap. Remember, a Sensor Jammer works by flooding space with high-powered "noise," in an attempt to overwhelm another ship's sensor system. The enemy may not be able to detect you, or even identify you, but they will know that there is something there, and furthermore, they will know exactly which direction it is in. If they dislace laterally to establish a baseline, some elementary math will tell them exactly where you are! 8o

Don't say it's impossible; U.S. Navy Sonar Operators do it on a daily basis.

Some feel that this unecessarily complicates things, but I want my players to fear the Empire. The Empire is big, they're tough, they're...well, they're not stupid, just arrogant and over confident, and adhere a little too closely to "doctrine" when imagination and innovation are called for. This shouldn't make them a doormat, in my opinion. Stealth and guile are called for, as going up against them with anything less than equivalent firepower is suicide. :raised:

If you and your players use these expanded Sensor rules, you can heighten the tension/drama, and, if your players are smart, use these rules to actually sneak past Imperials rather than using GM's fiat to say whether or not they do (if it's plot essential, you as a GM can still fudge in favor of the PCs).

Enjoy!