The Pentagon War game

by Roger M. Wilcox
Originally begun on 27-December-1983

This webpage was last modified on 10-April-2002


This is what this game is all about: the ancient fallacy of war.  After all rotation, acceleration, self-destruction, and movement for an impulse is done, players may declare any and all missiles, drones, and liquid metal gun bolts they are launching.  Missiles may be launched separately or all at once (although missiles in the same hex are quite volatile), but no more than [size class] drones may be launched during one impulse.  For example, a size class II spacecraft cannot launch more than two drones per impulse.  This is about the only advantages a large size class gives to a spacecraft.


Every spacecraft in the game has a size class from I up depending on how many boxes (spacecraft systems) it contains.  This size class determines how much power it takes for life support, how fast it may launch drones, what its minimum number of engine systems is, and how easy it is to hit.  Drones and missiles — since they are represented by counters and may be fired upon — each have a size class as well; however, they are size class 0, making them the hardest things to hit in the game.

The number of boxes on the SSD of the spacecraft, with the exception of the boxes in the radar track, determines the size class of that spacecraft as follows:

size class I: up to 80 boxes [escorts]
size class II: 81-160 boxes [cruisers]
size class III: 161-320 boxes [dreadnoughts]
size class IV: 321-640 boxes [gate guards]

Rarely did mobile spacecraft reach size class IV, and only once during the Pentagon War, in the case of the Human-Centaurian triple ramscoop "Defender," did any spacecraft exceed it.  Should a unit with more than 640 non-radar boxes be used in this game, it will use the formula established above to determine its size class, with one added to the size class for every 2x the number of boxes on board (641-1280 boxes would be size class V, etc.).


Usually, most units not friendly to one another will be aware of each others' presence.  Reconaissance is pretty accurate, radar is effective out to very long ranges, and non-movable bases have a tendency to stay in the same spot where you last saw them.  However, there are some cases (such as when a spacecraft is invisible to radar) where one side will not be aware of the other.  There are even cases when neither side is aware of the other, such as when both are radar invisible or a planet blocks line of sight.  In these circumstances, the positions, facings, and velocities of all non-detected units are kept track of secretly by the owning player.  The opposing player does not get to see the Acceleration Record(s), and counters are not placed on the map until an enemy vessel notices these units.

A unit is automatically detected by the opposing player, and thereby placed on the map, if any of the following situations occurs:

  1. The unit allocates power to ECM or ECCM.
  2. The unit uses active fire control (i.e. radar) in an attempt to achieve a radar lock-on to the opposing vessel, whether or not the lock-on attempt succeeds.
  3. The unit fires any weapons or launches anything.
  4. An opposing vessel achieves a radar lock-on to the unit (see below).
  5. The unit passes within five (5) hexes of an opposing vessel.  (Radar invisibility does not prevent a spacecraft from reflecting visible light.)


At the beginning of each turn during the radar lock-on phase, all units which declare that they are using active fire control must check to see if they have "locked on" to the enemy.  For each such unit, the owning player rolls one 6-sided die.  If the result is less than or equal to the highest undestroyed number on the "radar" track, lock-on has been achieved.  Most radar tracks start with a "6," so that lock-on is automatic unless this track is damaged.

If lock-on is not achieved — and lock-on is automatically not achieved if the player specifically declares that his spacecraft will not be using active fire control — the following restrictions apply (see the appropriate rules section later on to find out what these mean):

  1. No seeking weapons (missiles or liquid metal guns) may be fired.
  2. An additional -1 is added on, in addition to the normal range penalty, for direct-fire weapons' die rolls.  Effectively, direct-fire weapons aim as though their targets were twice as far away as they actually are.
  3. The number of point defense boxes of the failing spacecraft is halved (to determine the P.D. rating for that turn).  Round fractions of one-half up.
  4. Drones belonging to the failing spacecraft share its additional -1 direct-fire range penalty and halved point-defense disadvantages.


Most weapons in this game are direct-fire weapons; that is, the results are determined as soon as they are fired.  These weapons are: lasers, proton cannons, electron cannons, acid gum guns, and radiation guns.  Missiles and liquid metal gun bolts are seeking weapons; and while point defense is technically direct-fire, it's treated differently than the other direct-fire weapons and is not classified with them.

Every direct-fire weapon has a firing arc that says where it may fire.  The firing arcs used in this game are: left-front (LF), right-front (RF), left (L), right (R), left-aft (LA), and right-aft (RA).  These firing arcs extend from the hex the spacecraft is in (all direct-fire weapons may fire at anything in their hex), out along the rows of hexes going in the six directions.  If a spacecraft were facing direction "A", its LF firing arc would cover any spacecraft within the boundaries of the row of hexes going in direction "A" and the row of hexes going in direction "F".  Note that the firing arcs overlap.

There are shorthand names for composite firing arcs, since most weapons have more than a 60 degree arc of fire.  LF+RF form the front double arc (F2).  LR+RR form the aft double arc (A2).  L+LF+RF+R form the front quadruple arc (F4), while L+LR+RR+R form the aft quadruple arc (R4). LF+L+LR make up the left side triple arc (L3); consequently, RF+R+RR make the right triple arc (R3).  The front 180° arc, extending along the lines between hexes rather than a hex row, covering the hexes it bisects, is called the front triple arc (F3); it counts as three firing arcs.  The aft 180 degree arc is, of course, the aft triple arc (A3).  Although not recommended for weapons design, a single 60° arc facing directly forward would be the front arc (F), and a single 60° arc facing directly backward would be the aft arc (A).  Like the F3 and A3 arcs, these would end in hex boundaries, not rows.

When a direct-fire weapon is fired, two dice are rolled and added up.  To their sum is added the size class of the target spacecraft.  The range penalty (see chart) is further subtracted from this, and the final result of [2d6 roll] + [size class of target] - [range penalty] is catalogued on either the chart of the firing weapon or against its "hit number".


Proton cannons, electron cannons, and acid gum guns are "bolt"-style direct-fire weapons.  They either hit their target or they miss; there are no "degrees" of how well they hit.  For this reason, they have a "basic hit number" listed.  If the modified dice roll is greater than or equal to this number, the weapon scores a hit; if it is less, the weapon misses.  The damage of hits by proton and electron cannons diminishes with range, however.

Lasers and radiation guns are "beam"-style direct-fire weapons.  Instead of a basic hit number, they have a range of damage they can do.  Just catalog the modified dice roll against their chart to arrive at the number of damage points done.  However, since size class 0 objects have no structural strength when compared to spacecraft, any hit will destroy them; against these size class 0 targets, beam-style direct-fire weapons do have a basic hit number just like bolt-style direct-fire weapons.


Radiation guns require two turns of continuous changing to fire.  Lasers, electron cannons, proton cannons, and acid gum guns, on the other hand, may be fired as often as once per turn.  This presents a rather unrealistic situation if a weapon is fired on impulse 12 of one turn and then immediately again on impulse 1 of the next turn.  For this reason, weapons capable of a maximum fire rate of "once per turn" may not fire for at least three impulses from the time they were last fired to the time they can be fired again.  Thus, if a spacecraft had one left-aft firing laser and fired this on impulse 11 of turn 5, it could not fire this same laser again until impulse 3 of turn 6, after three impulses had elapsed where that particular weapon had not fired.  If the laser in question had been fired on impulse 12 instead, the owning player would have to wait until impulse 4 of the next turn to fire it again.

Magnetic beams may only be "fired" as often as once per turn, also (either to attempt to grab a unit or to atttack a liquid metal gun bolt).  Thus, they must also be inactive (not fire) for three impulses before they can fire after being used.

Obviously, if a weapon takes more than one turn to arm and fire (as is the case with liquid metal guns and radiation guns), it is going to have to wait at least three impulses between firings anyway, so this rule is a moot point as far as they are concerned.


Missiles and liquid metal gun bolts home in on their target.  When they are launched, their counters are placed on top of the launching spacecraft, their targets are (secretly) declared and may not thereafter be changed, and their initial heading is selected.  Missiles may be targeted in any direction, but liquid metal guns may only fire on targets within their launcher's firing arc.  Since they have no outside control, these weapons thereafter "home in" on their target, moving forward, in whatever direction their counter is facing, on every impulse they are to move.  They may change heading by one hexside (60°) every impulse; since facing is unimportant to these weapons, their counters face whichever direction their velocity components add up to, thus eliminating the need for extensive bookkeeping.

When they enter the target's hex, they attempt to ram (q.v.) their target.  If a liquid metal gun bolt misses its ramming attempt, it will double back and try to ram its target a second time.  Missiles may be pre-programmed to double back if they miss their targets, or they may just detonate and inflict half their warhead strength on their target and on everything else in their targetís hex.  If the seeking weapon successfully rams its target, it delivers its damage — although the strength of a liquid metal gun bolt may be lowered by range and proton cannon fire, and missiles may be stopped short by point defense.  A missile is destroyed before it reaches its target explodes, and everything in the missile's hex takes half its warhead damage.

Characteristically, missiles travel at speed seven and liquid metal gun bolts travel at speed twelve.  If power is applied to missiles, and if this option is used, they may be "rail launched" by a one-use electromagnetic launcher at speed twelve.  There are also other missiles that may be purchased for spacecraft that naturally travel faster or slower.  Missiles further have a limited duration, thanks to fuel limitations, and thus may not travel more than 30 hexes before they expire (they may be detonated at this point).  Again, other makes of missiles may have different durations.

Liquid metal gun bolts are the only objects in the game that are immune to the effects of most weapons.  Only proton cannons can effectively disperse the matter and magnetic field of a liquid metal gun bolt; any other weapons will have no effect.  For every 2 points of damage scored by a proton cannon against a liquid metal gun bolt, the bolt's damage will be reduced by one point when it hits its target.


Point defense is machine guns, short-range conventional missiles, and low-power energy weapons used to attack weak targets in the spacecraft's hex.  Since its procedure is different from any other weapons', it must be classed separately.

Each spacecraft may have only one point defense system; however, this system may consist of any number of boxes.  The point defense system has a point defense rating, determined as follows: add up the number of undestroyed point defense boxes on board the spacecraft, and if the number is greater than 5 assume it to be 5.  This may sound trivial, but when point defense is fired at more than one target in an impulse, it's the number of boxes that's effectively reduced by 1 to determine the rating, not the rating itself.

hile direct-fire weapons must be fired at the end of an impulse, point defense is fired immediately after the movement segment, and thus may be fired before an enemy unit (including a missile) gets a chance to ram.  It may be fired any number of times during the Point Defense segment, at any target in the same hex as the spacecraft.  When fired, roll a single die (not two dice as with direct-fire weapons), subtract the size class of the target, and compare this with the point defense rating.  If the rating is greater than or equal to the modified roll (i.e. the modified die roll is less than or equal to the rating), the PD has hit its target and scored one (1) point of damage.  Note that this is sufficient to destroy any size class zero target; note also that this is the only thing which may be fired at missiles by their targets when the missile reaches the target's hex.  Of course, even if a missile is destroyed, it explodes and all spacecraft in its hex take half its warhead strength in damage.  Each object in the spacecraft's hex may be fired at by point defense only once per impulse.

The first object fired at by point defense during any given impulse is fired at with the PD's full effectiveness.  The second object fired at during the same impulse is fired at as though the point defense system had one less operational box.  Since a spacecraft's point defense rating can never be higher than five, this reduction of effective boxes will not diminish the point defense rating of a spacecraft with six or more PD boxes.  The third object fired at during the same impulse is fired at as though the PD system had two less operational boxes.  The fourth is fired at as though the PD has three fewer operational boxes, et cetera.


Now that you know how to dish out damage, we'll show you how to take it.  All damage incurred in a single impulse is incurred simultaneously, during the damage assessment segment, after all spacecraft have had a chance to move and fire.  For every unit of screening a spacecraft has, the amount of non-radiative damage it receives is reduced by 1 point.  If this difference is zero or less, the spacecraft takes no physical damage.  If there is not enough screening to cover the amount of non-radiative damage incurred that impulse, then the remaining damage is applied to the armor facing the direction of the attack.

Armor is numbered #1 through #6, based on the relative direction it faces:

Relative Directions
Which armor (#1 through #6) is hit is determined as follows: draw an imaginary line between the centers of the attacking hex and the target hex, and from there determine which of the target's hexsides has been crossed.  Each armor section is assumed to give a 60° arc of protection against the hexside it faces.  If the imaginary line goes exactly between two hexsides, determine which armor would be hit if the spacecraft that was going to move next were to move.

If the firing spacecraft and the target spacecraft are in the same hex, as in the case of a missile or a liquid metal gun bolt striking its target, judge which armor is hit from their positions before the current impulse — as far back in time as necessary until they weren't occupying the same hex.

If fire has hit the spacecraft from more than one direction during an impulse, and the spacecraft has screens, a little averaging must be done.  Total the damage scored against the spacecraft, subtract the screen rating from this total, and divide the damage against separate armor sections in proportion to the original attacks.  You may have to use [amount of damage from one direction] divided by [total damage] to determine the ratio of damage against the armor.

EXAMPLE: Our old friend the Aklinon is attacked by two electron cannons and a proton cannon from direction "1" that do 16 total points of damage.  Earlier that impulse, a missile entered its hex from direction "3", and the poor sucker missed its point defense roll so the Aklinon now takes the full 12 damage points from the missile's warhead.  The player totals the damage (16+12=28) and subtracts the Aklinon's screen rating (8).  Now, 20 points must be allocated between armor #1 and armor #3 in the same exact proportions that the 28 damage points struck the spacecraft.  This is done as follows: 16/28 = 0.571 (four-sevenths), 20 x 4/7 = 11.4, which rounds to 11 points of damage against armor #1; 12/28 = 0.429 (three-sevenths), 20 x 3/7 = 8.5, which rounds to 9 points of damage against armor #3.  How about that, all 20 points were used up!  The Aklinon must now cross off 11 boxes from #1 armor and 9 boxes from #3 armor.


Lasers and radiation guns, which are classed as "radiative" weapons, are the exceptions to the above rules on screening.  Since neither fires any kind of physical object, electromagnetic screens do not interfere with them; lasers and radiation guns totally ignore screens and are applied directly against the target's armor, if any.  Since they don't interfere with screens either, their damage doesn't have to be added together and "apportioned" among different sections of armor if their target is hit from multiple directions.

If the armor they hit is "new," however — i.e. it has no undestroyed boxes — then the first five points of radiative damage incurred against that section of armor during that impulse are ignored.  Effectively, each undamaged section of armor has five points of "screening" that only works against radiative weapons.  This is because spacecraft designers know about radiative weapons' ability to sidestep screens, and make up for it by "mirroring" the surfaces of combat craft with chrome or other shiny metals.  In order for radiative weapons to damage new armor, at least six points of radiative damage must be scored against that section of armor in a single impulse.  After the armor has been damaged, though, it loses its reflectiveness and can be further damaged normally.

Radiative weapons may, at the firing spacecraft's option, be timed so as reaching their target "last" during an impulse.  This way, other non-radiative weapons may first have a chance of damaging the armor, thus leaving the radiative weapons no reflective surface to contend with.  This decision must be made beforehand, during the fire decision segment of that impulse.


In the event that the screens and the armor combined aren't strong enough to stop all the damage, the remaining damage is applied internally.  For every point of interior damage, roll 2 dice of different color, and look up the result on the Damage Allocation Chart.  That damage point will destroy one box belonging to the system indicated.  If the listed system is not available, roll the dice a second time, re-rolling them if they happen to generate exactly the same roll (not the same type of system hit, the same pair of numbers).  If this second listed system is not available, re-roll a third time, discarding previously rolled number pairs.  If this third system isn't available to be damaged either, roll a fourth time, again discarding earlier results.  If that fourth system rolled still isn't available to be damaged, the hit must be scored against Final Damage.

If the last Final Damage box has been destroyed and the spacecraft receives another Final Damage hit, the spacecraft is destroyed, and will (optionally) explode using the self-destruction rules.

If interior hits are scored against secondary weapons (secondary weapons being lasers, electron cannons, and proton cannons), the weapon(s) must be able to fire in the direction the attack came from; i.e. a spacecraft facing direction "A" in hex 2020 that's struck from hex 1917 and takes an interior "laser" hit may apply this hit to any laser that can fire in the L firing arc.  If no such weapon is available, the next level on the chart is used.


Although you could mark a system as destroyed with an asterisk, a capital "D," or a smiley face in bright red crayon, it is important that your opponent knows which systems you have marked as destroyed.  The SSD sheets are public, after all.  To this end, the following system of notation has been developed and should be used by all players unless they agree otherwise before the game begins:
A box with no markings in it is not damaged.  It is also "full"; that is, if it is a missile box, there is a live missile in there.  These boxes may be damaged by interior hits, noted by an X.
A box with a dot in it is not damaged, but is empty.  This notation must be used with missiles, drones, fuel tanks, and cargo.  It may also be (but isn't required to be) used with secondary weapons to indicate that that particular weapon has been fired during the current turn.  These boxes may be damaged by interior hits (use an X).
A box with a slash through it is "marked as destroyed," but has not actually taken any damage.  This notation is used with guns.  Unlike boxes with dots in them, these boxes are ignored during the damage allocation procedure.
A box with an X through it is actually destroyed, whether by taking damage during the current scenario or by already being that way at the scenario's start.  Like boxes with slashes in them, these boxes are skipped at damage allocation time.


A lot of internal damage, if it doesn't destroy a spacecraft outright, can seriously impair its ability to function in a combat situation.  A spacecraft is considered crippled if any of the following conditions are true:

  1. Over 50% of its internal systems are damaged.  Armor, final damage, and radar do not count.
  2. All of its control systems have been destroyed.
  3. No more than 20% of its total weapons capability is left undestroyed.  Capacitors destroyed in excess of functioning secondary weapons' power requrements count as destroyed weapons capability.
  4. It has taken any Final Damage hits.

Crippling an enemy spacecraft is usually worth some victory points, depending on the scenario.


When a spacecraft self-destructs or a missile is detonated or destroyed, it explodes.  All explosions in this game are treated in a similar fashion:

An explosion has a basic strength.  In the case of a self-destructing spacecraft, this is calculated from the undestroyed systems on board.  In the case of a missile, this is half its warhead strength.  The strength of an explosion is equal to its basic strength in the hex it goes off.

As the distance from the explosion increases, its effect diminishes.  In all hexes one hex away from the explosion, the strength of the explosion is its basic strength minus eight.  Two hexes away, its strength is its basic strength minus sixteen.  At three hexes distant, its strength is its basic strength minus 24.  This reduction of the explosion's strength by 8 points per hex away continues outward until the strength is zero or less, at which point everything from there on out is "out of range."

All objects within range of the explosion, except for liquid metal gun bolts, are affected — friend or foe.  Since drones and missiles inside a launching spacecraft are not considered separate objects, they are protected.  Likewise, two spacecraft attached to one another are considered a single object, as one spacecraft "shields" the other.

Any object of Size Class I or greater (except liquid metal gun bolts) merely takes the explosion's strength in damage points, inflicting the damage (against its screens first, of course, if it's operating any) during the damage assessment segment.

Size Class 0 objects, such as drones and missiles, are normally destroyed by taking one (1) damage point.  This would ordinarily mean that any explosion, no matter how weak, would vaporize all size class 0 targets within range.  Instead, to make things fair, size class 0 objects in explosions merely have a chance of being destroyed.  Roll two dice, add them up, and if their sum is greater than the strength of the explosion in the size class 0 object's hex, it has survived; otherwise, it has taken that one fatal point of damage and is destroyed.  Note that if this object is a missile, this missile will explode for half its warhead strength as well.  Very large pyrotechnic cascades are possible with a hex full of missiles.

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