These Traffic and Chase rules give detail to every possible aspect of overland travel, from random traffic generators to the reactions of other drivers, to common road hazards. Obviously using all the rules at once may bog down your game, feel free to pick and choose the rules as you see fit to suite situational needs.

Random Traffic Generator

Cars sharing the road in 10 round (30 second) increments.
1Road Clear
2-61D6 Vehicles
7-92D6 Vehicles
103D6 Vehicles
Daytime (normal hours 5-7AM, 9AM-3PM and 6PM to 9PM)default
Rush Hour (7AM-9AM and 4PM-6PM)doubles the number of vehicles rolled
Nightime (9PM-12PM)1/2 of the vehicles rolled (round down)
Late night/early morning (12PM-5AM)1/3 of vehicles rolled (round down)
High population Areax2 Vehicles rolled
Rural Area1/2 vehicles rolled (round down)
Desolate area (interstates between cities, extreme back roads, etc...)1/4 vehicles rolled (round down)
Dirt Roadsraise difficulty modifier level by 1
Road in severe disrepairraise difficulty modifier level by 2
Light rain, snow-10% of vehicles on road (round down), treat speed limit as if -15 km/h posted, increases difficulty modifier level by 1
Heavy Rain, Snow, Ice, fog, and Sandstorm-50% of vehicles on road (round down), treat speed limit as if half posted, and Difficulty Modifier level raises by 2

For every 2 vehicles over 5 per lane in an increment, treat posted speed limit as being 10% lower in that lane.
Roll on the table above once for traffic moving in your direction, and again for the traffic in the oncoming lanes.
The default is for a 4-lane road (2 lanes moving your direction, 2 lanes oncoming). For every additional lane add 1D6 vehicles.

Traffic Random Vehicle Generator

2-3Compact Car, Midsize or Car Sedan
6Luxury Vehicle or Sportscar
7-8SUV, Pickup Truck or Minivan
9Large SUV, Van or Light Truck
10Semi Truck or Large RV

Traffic is always assumed to be going the posted speed limit (or the speed limit as modified by road, traffic, and weather conditions). Individual traffic however, may deviate by 1D10 km/h over or under the posted speed limit for an addition realistic touch).

For every 10 km/h difference over the posted speed limit, drop the re-roll time by 1 round (3 seconds), to a minimum of 1 round (3 seconds). Meaning if you are going the posted speed limit of 65 km/h, then you only re-roll the traffic generator every 10 rounds (equal to 30 seconds game time). However, if you are doing 110 in a 65 km/h zone, then you re-roll traffic every 3 rounds (12 seconds). If you are doing 150 or more in a 65 km/h zone, you re-roll every round (3 seconds), same as if you are doing 185 km/h in a 110 km/h zone.

Km/h over posted speedRe-roll times modified by speedKm/h over posted speedRe-roll times modified by speed
Posted speed10 rounds (30 seconds)+50 km/h5 rounds (15 seconds)
+10 km/h9 rounds (27 seconds)+60 km/h4 rounds (12 seconds)
+20 km/h8 rounds (24 seconds)+70 km/h3 rounds (9 seconds)
+30 km/h7 rounds (21 seconds)+80 km/h2 rounds (6 seconds)
+40 km/h6 rounds (18 seconds)+90 km/h1 round (3 seconds)


Random side street availability

For every traffic re-roll increment (roll for traffic at each street only if characters are turning or that street has right of way).

Roll 1D6CityUrban HighwayRural HighwayRural Road (50% chance side road is dirt)
3-421 exit rampNo1 road
531 exit rampNo2 roads
642 exit ramp1 exit ramp3 roads

Chase Position

For every 15 km/h over the speed of traffic an individual vehicle is traveling, it may pull ahead at 1 car length per round. For vehicles involved in a chase or race, this rule only counts towards vehicles moving at the posted (modified) speed limit. Involved vehicles move relative to traffic, their position relative to each other is determined by individual speed, acceleration, and other modifiers.

Round by Round

Acceleration : roll a drive check, on a successful roll, every point over the target difficulty allows you to accelerate 10 km/h. Failure of this roll indicates a character has become nervous or unsure, and decelerates by 10 km/h instead. Alternatively, at any time a a character may opt to decelerate safely at up to half his listed deceleration.
Making a full deceleration (equating to slamming on the brakes) requires a roll 1 difficulty level higher than the standard for driving (with modifiers for speed, weather, road conditions and traffic included). Slamming on the brakes also forces any vehicles behind you and within your threat range, to make an immediate maneuver roll with additional modifiers due to distance included.

Threat Range

Every 15 km/h a vehicle is traveling increases the threat range by 1 vehicle length.
Vehicles in a threat range have their difficulty modifier level increased by 1 for every vehicle length they are nearer to the the vehicle in front of them.
When a vehicle gets within 20% of its maximum speed, increase the difficulty modifier by 1 level.
For every 30 km/h over 130, increase the difficulty modifier by one level (add or reduce 15 km/h to the 130 for every bonus or minus to maneuverability a vehicle possesses).


This is the speed your vehicle must reduce to in order to turn without penalty, for every point of maneuverability, you may increase this speed by 10 km/h (for the purposes of this, count all 0's as being -10 consecutively). If top speed is zero, the vehicle effectively comes to a complete stop.

RadiusTop SpeedRadiusTop Speed
15 degree110 km/h105 degree15 km/h
30 degree95 km/h120 degree0 km/h
45 degree80 km/h135 degree0 km/h
60 degree65 km/h150 degree0 km/h
75 degree50 km/h165 degree0 km/h
90 degree30 km/h180 degree0 km/h

Reactions of non involved drivers to vehicles involved in chase

Roll 1D10 on the following chart whenever an involved vehicle makes any maneuver that would cause a non-involved vehicle to react.

1D10Reaction Result
1Driver panics, loses control of vehicle (roll on vehicle fumble table)
2Driver not paying attention, cannot react or evade
3Road Rage, driver purposely does whatever he can to hinder involved vehicle, 20% chance he will join chase
4Driver speeds up
5-6Driver slows down
7Driver moves out of way violently, if driver is in outside lane he will move onto shoulder or sidewalk, if he is in inside lane he will move into oncoming traffic, if multiple lane, he will move into adjoining lane regardless of traffic.
8Driver slams on breaks
9-10Driver moves out of way easily

City or rural side street

At every city or rural side street encountered roll 1D10. If you are currently on a main thoroughfare, re-roll a 3-5 once and keep result.

1-2Side streets have stop signs
3You have stop sign
4-54-way stop sign
6-10Stop light
For a stop light roll 1D6 : 1-3 green, 4 yellow, 5-6 red (if yellow it will change to red in 1D6/3 rounds (3-6 seconds)).

Random Road Occurrences

Roll once every ten increments of random traffic, only during actual chases, or alternatively, a GM may simply use these instances as a guide for adding flavor a chase.
For every increment of random traffic rolled, there is a 10% chance of police presence.

1-3Driver ahead slams on brakes
4-10Opening in traffic, road clear ahead for 2 increments (comes in to play next increment)
11-20Vehicles ahead of you are side by side and blocking you from passing
21-24Opportunity for cinematic maneuver (ramp allowing for jump, vehicle with loose cargo, etc...) (comes into play next increment)
25-29As you move to pass a vehicle it suddenly swerves into your lane (18 difficulty to avoid)
30-35Traffic closes behind you, hindering pursuit for 2 increments
36-38Animal, person runs out into road ahead of you (18 difficulty to avoid)
39-42Vacant lot, open field on side of road
43-45Something falls from a vehicle in front of you (20 difficulty to avoid)
46-50Emergency vehicle, lights and siren on, pulls onto road ahead of you, moves 30 km/h faster than posted speed limit, stays on road for 2D10 rounds
51-55Collision between one or more vehicles in front of you (23 difficulty to avoid)
56-60Road ends in a T-Junction (if on rural road, road becomes dead end, if on interstate, ignore and re-roll)
61-65Road damage (large potholes, etc...)
66-72Road changes size (even larger, odd smaller), roll 1D6/2 to determine additional lane increase/decrease. Even numbers always result in the lanes distributed equally to both outbound and inbound lanes, if the roll is odd, the GM determines placement of the lane (if the road gets smaller and decreases to 1 lane, the road becomes 1-way).
73-78Oil, ice (15 difficulty to keep control, or glass, nails, debris, etc... (10% chance of blowout)
79-84Sharp curve ahead, increases difficulty modifier by one level.
85-87Driver from side street runs light or stop sign (24 difficulty to avoid)
88-93Traffic jam ahead, all traffic comes to a complete stop
94-96Oncoming traffic suddenly swerves into your lane (difficulty 26 to avoid)
97-100Vehicle broken down in middle of the road

Driving Off-Road

Fairly flat field+1 difficulty modifier level
Partially wooded, rocky, and/or hilly terrain+2 difficulty modifier level
Densely wooded, very rocky, and/or steep hills+3 difficulty modifier level
Flat, hard packed desert+0 difficulty modifier level
Loose sand desert+2 difficulty modifier level
High dunes, drifting sands desert+3 difficulty modifier level

Off-road capable vehicles treat off-road conditions as being 1 difficulty modifier level lower.
Treaded vehicles treat off-road conditions as being 2 difficulty levels lower.

Vehicle Quality Rating

The GM should assign all primary vehicles (Characters Vehicle, involved NPC vehicles, etc.) a quality rating.
Breakdown chance is rolled once per day vehicle is used. There is ALWAYS at least a 1% chance of vehicle breakdown.
For every 20% of SDP damage taken a vehicle drops one category and must make an immediate breakdown chance roll.

Quality RatingChance of breakdown per day
Last Legs20%
Used and Abused15%
Showroom Quality1%

Other quality rating modifiers
New vehicle (1 year old or less)-10%
Used (2-10 years old)+5%
Well used (11-20 years old)+10%
Classic (21-30 years old)+15%
Antique (31+ years old)+20%
Standard maintenance0
Well Maintained-5%
Lovingly maintained by top grade professional mechanics-10%
No Maintenance+10%

A brief word on aerodynes

AV's, advanced hovers and helicopters must adhere to the same penalties applied to ground level traffic when in an urban metropolis environment and involved in a chase. While aircraft have the luxury of traveling above the rooftops in normal situations, when involved in a chase, to be effective they must follow the streets that the vehicles they are pursuing are on. This is really only important in a metropolis type setting, where skyscrapers and other tall buildings are prevalent. In a smaller town, or even in a heavily urbanized area where the buildings are rarely more than 4 stories tall, Aircraft are not constrained by these rules. Alternatively, even in an urban metropolis, the Aircraft may gain elevation to escape the close confines, but this will take him out of attack range of the ground, and it will add two levels of difficulty to all rolls attempting to spot and follow the ground vehicles due to distance and altitude. If the chase is between aircraft alone, then rules apply as normal. All air traffic is to be treated as if having rolled 1D6 less than the result on the random traffic generator.

All AV's are equipped with a GPS linked Collision Avoidance (CAV) system. This system is one of the most advanced navigation systems in the world and monitors the activities (altitude, speed, and direction) of all aerodynes, helicopters, dirigibles, and other aircraft within a 10 km radius (the military version is good to 15 km). Police Aerodynes and some ground vehicles can scan for the system, and every landing pad in the city is set up to detect the CAV System as well. Driving an AV in an urban environment (defined by law as any population center with at least 5000 citizens in a 15 km radius) without the CAV system is a felony punishable by up to 20 years in prison. Also, since all AV's are required to have the system installed during manufacture, it requires an illegal modification (High Difficulty) to remove it. Though scratch building an AV without it is possible. Due to powerlines, bridges, overpasses, streetlights, walkways, and the like, it is extremely inadvisable for any aircraft to even attempt to operate lower than 15m from the ground in an urban environment. Doing so immediately raises the Difficulty Modifier level for the AV to Very Difficult, in addition to whatever modifiers it may be facing.