In a pursuit, there are the chased and the chaser; in The Adventures of Indiana Jones, the terms are Leader and Follower, respectively. Distance is measured in units of 25 feet called Areas. The Referee's Screen presents a table that converts miles-per-hour into areas-per-turn in increments of 10 mph. (A Turn is five seconds.)
In any given turn, the distance of the Leader from the Follower equals the Follower's Chase Rate subtracted from the Leader's Chase Rate. The Leader has a number of Areas as a Head Start. The sum of the Leader's speed and Head Start is his or her Chase Rate for the first turn of the chase; the Follower's Chase Rate equals his or speed. To determine Chase Rate on subsequent turns, for both Leader and Follower, speed is added to the prior turn's Chase Rate.
According to the rules:
It doesn't matter if your characters are using cars, horses, or their own feet in a chase. You run chases the same way for all three.Despite this assertion, the rules primarily address vehicle chases. Vehicles have the following specifications: Acceleration, Breaking, Maximum Speed, Redline Speed, Turn Speed, and Vehicle Rating. If a vehicle tries to turn when in excess of its Turn Speed, the driver must make a Movement Check. If successful, the turn is accomplished without incident; if unsuccessful, “your character loses control and has an accident.” The vehicle's speed is added to an accident roll. Results on the Accident Table range from 'skid' to 'flip and roll'. When a vehicle travels faster than its Redline Speed, the driver's Movement Rating is halved. Vehicle Rating “is a measure of a vehicle's durability.”
If light damage is inflicted upon a vehicle, its “Maximum Speed is reduced by 10 mph.” If a vehicle suffers medium damage, “The vehicle's speed is cut to half of its normal Maximum Speed.” When a vehicle takes serious damage, it “stalls out and [slows] to a complete stop.”
The Adventures of Indiana Jones has a Chase Flow Chart (presented above). It consists of twenty-five circles identified by letters A through Z (with the exception of O). Twenty-one of the circles represent intersections, three represent Hazards, and one is a dead end. The Hazard Table is shown below; however, the rules state, “The Referee may also create his own Hazards.”
The Judge's Survival Pack includes additional rules and material regarding chases.
First, there are five more Chase Flow Charts: one for “citystreets,” one for countryside, and three for buildings (“mainfloor,” “midfloor,” and rooftop). Additionally, there are Hazard tables for “countryroad” (with results like blow out, cloud of dust, and bridge out!) and buildings (with results like loose carpet, cleaning lady, and “laundry in hall”). (Incidentally, The Fourth Nail Adventure Pack includes several Chase Flow Charts, including charts that represent Barcelona.)
Second, chase participants can attempt “shortcuts.” With a successful Movement Check, the character gains “spaces” (either 2, 4, or 6). Although unstated, I suspect that for vehicle chases, “space” means Area and for foot chases, “space” refers to Square (i.e., five feet).
Lastly, the Judge's Survival Pack provides rules for stunting. For “wild car chases,” characters can do things like attempt “skid turns and bootleg 180 degree turns” (succeed with a Movement Check or else roll on the Accident Table) or jump an obstacle (“there must be a ramp in front of the obstacle, the driver must be going Redline speed, and he must make a Movement check at × ½”). Rules are also supplied “for overcoming obstacles in a foot race.” For instance, actions such as “Sliding, Swinging, Vaulting, and Tackling require a Movement check at × ½ to maintain control and not get hurt.” Another rule helpfully explains, “Walking a ledge, Jumping High, and Controlling a fall may require a normal Movement check or one at ×½ or ×¼ depending on how difficult the situation is.” So, in short, engaging in a Movement 'stunt' may require a (possibly modified) Movement Check.