The formulation of specific rules for a game will depend on the choices that have been made for its overall structure. The stucture may range from a seminar game with a dozen players and a facilitator who deals with the rules to a massive game with hundreds of players scattered over many sites. There are also games with paper maps and cardboard markers where resolution of action often uses dice and lookup tables, and games with considerable computer support, where algorithms and databases comprise most of the rules. Providing a compendium of rules that can be applied to such a diverse spectrum of structures is daunting.
Rather that providing such a compendium, a list of rule areas is offered below as a checklist. Many of the rule areas include references to text books or ongoing research that will provide detailed, sometimes daunting, descriptions of how to model the given phenomenon. This checklist can be used for a specific game design to detect if some critical area may have been overlooked.
The summary of rule areas below are generally for the platform level -- where a platform could be a ship, an aircraft, or a land vehicle. A single dismounted soldier can also be consideed a platform. It is possible for a platform to launch another platform that will in turn have its own platform-based rules, e.g., an aircraft carrier launching aircraft, or a troop carrier de-bussing individual soldiers.
In land-based wargames at lower tactical levels, rules are generally at the level of individual platforms. These platforms are generally vehicles, but "platforms" may also represent individual soldiers (or civilians). At the platform level, most rules are based on simple physics, e.g., ballistics or aerodynamics. For play above lower levels of tactical interaction, some aggregation will be necessary, say to determine what happens when two army divisions confront each other. So, in these cases, rules generally need to be aggregated to levels higher than platforms, e.g., platoons through brigades to armies. Aggregation may also be needed for the air and maritime environments as well. Aggregating a diverse set of sensors or weapons becomes complicated quickly and will not be covered here.
For an example of aggregation intended to reflect historical combat, see a board game called Normandy '44. The game is played on a hex-based map of the Normandy Peninsula with counters representing units at the battalion, regiment, and brigade levels. The symbols on the counters represent the unit's anticipated performance characteristics, as well as some other details.
Aggregating the effectiveness of historical units is difficult. But it is facilitated by the record that is generally available on the performance of these units in battles of the past. Even when such data may be lacking for a particular unit, there may be sister units with similar composition and training that can be used to estimate values for the given unit. The combat strength is certainly dependent upon the weapons in the unit, but may be adjusted for other factors, e.g., the quality of its leadership, its previous combat experience, the amount and rigour of training. Often game designers will debate at considerable length how to set the aggregated performance values for a given unit.
A counter, from the game Normandy '44 for the Canadian Sherbrooke Fusiliers , an armoured regiment, shows how combat strength is represented by a single number, "3" in the lower left-hand corner. In the lower right-hand corner is a value for movement allowance, namely "6". In this game, there are rules specifically for armoured combat and the number "3" between the combat strength and the movement allowance is used for this.
For units where there is little or no historical data, determining aggregated performance may be particularly difficult. This may be the case for current units that have no battle experience or for proposed units used in developing or testing concepts for the future. Since units that have untried weapons have no historical record, representing the performance requires prediction. Units have been given systems that incorporate advanced technology may appear to be on a route to improved performance. However there may be offsetting phenomena. For example, personnel in such units might find their hi-tech solutions are more fragile than traditional systems. The hi-tech systems may have poorer operational availability, or require more maintenance or training. The proponents of such systems can be overly optimistic about their performance in combat because they fail to appreciate the importance to personnel on the ground of aspects like simplicity, training, and maintainability. Also, military leaders may be challenged to find ways to best expoit the future technology so new systems may be under-employed or mis-employed. A consequence may be that units that have hi-tech systems do poorly against a foe that relies far less on technology.
Environment (terrain, weather, visibility, obstructions)
Terrain can be represented with a fairly simple map. For manual games, hex overprinting of paper maps has been common since the 1970s. The map for the game Normandy '44 (see image) illustrates this. This map gives an idea of water obstacles and the like. Since it is at a fairly small scale, micro-terrain issues like hedgerows are not obvious.
Performance in bad weather or during periods of darkness can be adjusted accordingly. There are opportunities to exploit some advantages from technology meant to overcome such conditions. For example, Western armies have deployed advanced sensors fairly widely, e.g., image enhancers, thermal imagers, ground-surveillance radars.
With the advent of computer-support and digital terrain, the representation of land features has become considerably more detailed. When playing on a computer-supported combat simulation, like Janus or OneSAF, the impact of matters like the terrain on movement and obstructions that imhibit visual detection can be represented with little or no human intervention.
In a manual game (again Normandy '44 is a good example), movement is generally governed by a movement allowance for a specifed time interval. Computer-based simulations generally handle movement rates aand remove this burden from the players. Determining appropriate movement rates may require support from detailed engineering models to ensure accuracy.
One well known model for this is the NATO Reference Mobility Model. Versions of this have been available for some decades and further development of the NATO Reference Mobility Model is in progress.
For ships and aircraft, platform simulators are often used within a war game. Given the sophistication of modern ship and aircraft simulators, these should provide an accurate depiction of the movement rates of the corresponding platform. Simulators are also available for land vehicles, but their movements are often affected by troops mounting or dismounting, or micro-decisions by drivers. So simply using simulator results for ground vehicles may give an optimistic impression of movement rates.
Natural or man-made obstacles will affect movement. For certain classes of vehicles some natural obstacles may be impassible, e.g., rivers. Some man-made obstacles like abatis or minefields may require special engineering equipment for army forces to overcome. If these obstacles are covered by fire, they may become particularly obstructive and lethal. Engineering studies may be required to determine what delays may be imposed by various obstacles.
Minefields can require extensive rules that depend on characteristics like density of mines, triggering mechanisms, and the nature of mine hunting, mine clearing, and mine neutralization equipment that can be used against them. Minefields bring in important psychological aspects: seeing some of their colleagues strike a mine tends to reduce enthusiasm in the rest to press on.
Some terrain may be littered with obstacles, e.g., in urban operations. Apart from mobility restriction, these obstacles can interfere with detection or inhibit use of some weapons. Often players can change the characteristics of obstacles within a game (explosives against buildings), so rules need to allow for this.
Detection (and false alarms)
Detection is a field that requires considerable sophistication in modeling such as that found in the ACQUIRE model. This model, or data derived from it, has been incorporated into many wargame simulations.
The complexity in detection rules is also due to the variety of sensors that may be available, ranging from the unaided eye to radar and other electro-optical devices. The ACQUIRE model, for example, deals with visual detection and military imaging systems, but other models will be required as well.
An aspect of detection that many rules (and simulations) overlook is false alarms. Many rules will have some conditional probability: if a potential target is present, then determine the probability it would be detected and draw a random number to determine if detection occurs. However, false alarms occur without a target being present, so this conditional probability is irrelevant for false alarms. Nevertheless they certainly occur in real life and they have generally not been studied to the point that there are agreed ways to represent them in game rules.
Rules for acoustic and radar detection (usually of ships or aircraft) may have paid the most attention to false alarms. Here, in simpler models, we call a detection if acoustic or electromagnetic energy goes above a specified threshold. This threashold can be set high (lots of detections, but many false alarms too) or low (fewer false alarms, but with the price of missing potential detections). With records of the fluctuations of acoustic energy (both for noise alone, and for signal plus noise) there will be times when a detection is triggered by noise alone (a false alarm).
Identification (and misidentification)
When a potential target has been detected, there remains an issue of "who is that?" Target identification has been studied extensively and there are models available.
One aspect that is often overlooked in rules is the possibility of misidentification, for example, mistaking "friend" for "enemy" and vice versa. The causes of this are numerous: lack of training, level of adrenaline. It remains a crucial, if understood phenomenon.
Engagement (direct and indirect fire, other fire support, air support)
Over many decades, the OR community has developed sophisticated models for engagement. The Army Materiel Systems Analysis Activity and Joint Munition Effectiveness Manuals provide extensive material on algorithms and data at the system level.
Apart from the firing system, the vulnerability of the target needs to be incorporated into the calculus of an engagement. When these targets belong to some enemy nation there is a need for detailed technical intelligence to know what kill mechanisms are most likely to counter a specific target.
Where the physical characteristics of a system determine are relatively well known, there may be engineering models for the system. Such models can be used to produced detailed tables of performance. In DoD the Army Materiel Systems Analysis Activity can provide detailed models and data for many systems.
An aspect of direct and indirect engagements that is hard to assess is suppressive fire. Here the objective of the firing side is to degrade the performance of the target force to a level where it cannot fulfill its mission. It is generally assumed that suppression ceases to be effective when it stops. However, there are many psychological aspects involved in suppressive fire so it its effectiveness is hard to judge based only on physical aspects. This can make its use within a wargame somewhat contentious.
Apart from the units that are available when a game begins, others may be introduced as the game proceeds. In a wargame, the availability of such reinforcements will rely on many factors, as they would in the real world. Players should be allowed access to reasonable reinforcements, but limited by appropriate factors, e.g., ability to move units that can be re-assigned as reinforcements, authority from higher command to commit some reserve forces.
Many games avoid the issue of reliability. This may be appropriate for games of short duration: an assumption may be that there is insufficient time for the usual wear and tear to degrade equipment. However in games where the duration may be more than a few hours, or where particularly high intensity operations are encountered, it will probably be more realistic to include a factor for equipment failure.
Apart from equipment, the reliability of personnel may also be a factor. However, for troops this is usually related to morale, see below.
Damage and repair
One of the best known situations of equipment casualty recovery and repair, is the return to operational status of the USS Yorktown between the Battle of the Coral Sea and the Battle of Midway. In Europe during World War II, the operational research section attached to Montgomery's 21 Army Group conducted a study of locations of workshops used to repair armoured vehicles, see Terry Copp's Montgomery's Scientists, pp. 409-414. Their study illustrates some of the trade-offs: workshops close to the front allow expeditious repair and return of tank casualties, locations too close to the front are susceptable to being overrun, workshops cannot repair tanks when moving to stay close to supported units, a lack of tank transporters may mean that operational tanks that are available cannot be positioned for best effect.
The ability to repair critical equipment and return it to operations may have little impact on a game dealing with a short-term tactical problem -- "you fight with what you've got". However for analysis of a campaign lasting more than a few weeks, rules may have to be developed that provide for equipment being repaired. In many situations, decisions by players on how much effort to allocate to equipment repair could have long-term consequences at the operational and strategic levels.
Personnel casualties are often reflected rather superficially in wargames -- they are simply counted and reported. However, casualties can often have a considerable impact on decision making on operations. At a tactical level, decisions to recover injured personnel can, for example, draw resources away from other initiatives. The US Air Force, for example, devotes considerable effort and resources to combat search and rescue (CSAR), looking for and recovering down aircrew. Likewise land-based units down to company level often include ambulence vehicles; since these are unarmed they may require combat vehicles to provide protection. Associated decisions are a matter of resource allocation, and can affect the outcome of games.
Beyond mere recovery of injured troops or downed aircrew, more resources may be needed for medical treatment and evacuation. Field hospitals then require protection to be provided by combat resources. A beneficial effect of casualty treatment is that personnel may be returned to operational status and contribute operationally later in a war game. And personnel who know that their commanders will go to great length to recover them and deal promptly with their injuries are expected to be have higher morale, and combat motivation.
Leadership and morale
Many volumes have been written on leadership and morale. But there is very little precise information on how to use this to create rules for war games. One assumption is that if a leader, particularly one with charisma, is in close proximity to a unit in a game, that unit will benefit in fighting capability or in willingness to pursue the objective after having taken casualties. Some simulations have morale settings where the capability of a unit will be influenced by a morale setting for it. However, there is little guidance on "where to set the needle on the dial". Compelling arguments have been made that elite units (like the US Rangers and UK SAS) will fight harder and longer than non-elite units (e.g., poorly trained conscripts), but where to set the scales for a set of rules is elusive.
For gaming, the impact of leadership and morale is most likely to be viewed as a matter of combat motivation: how willing are military personnel to engage in combat operations? Within the OR community, this received considerable scrutiny in Combat Motivation by Anthony Kellett. The book provides no magic solution, no rule-based procedure for predicting who will take the fight to the enemy and who will shirk their responsibilities under the stress of combat. It does however provide a very methodical and well researched account of the issues.
Since a primary focus of wargaming is the decisions made by players, playing war games is a useful process in assessing the quality of decision making. The challenge of capturing decision making procedures within wargaming rules remains largely unaddressed except in rather elementary situations.
Command and Control (team cohesion, situation awareness)
One approach to incorporating command and control into wargames is to cocoon a commander, staff, and their familiar C2 systems and feed them information from the wargame as if it were coming from superior, subordinate, and adjacent units. This approach dates back at least to the 19th century at the Naval War College. A staff worked in a side room isolated from the rest of the game apparatue and could only send and receive the messages they would expect in an operational setting.
Navies often design ships so their operations room or combat information center (CIC) can plug into a wargaming center ashore. Similarly army headquarters can deploy onto a training range and transmit and receive the messages to and from a wargame center that they would expect if it were real operations. And, for aircraft like AWACS, staffs can work on their (simulated) air picture without leaving the ground. Such subterfuges can come close to replicating many important aspects of a real-world situation. However, these methods generally do not reproduce factors like sleep deprevation, combat fatigue, or psychological stress that might generate command and control failures in combat.
In recent years there have been many worthy initiatives to develop models of situational awareness (SA) and to determine levels given command teams at critical times. Of the several models of SA, the Endsley model is the best known. While models of SA and methods for assessing it are still maturing, SA is still controlled in modern wargames much as it was by McCarty Little at the Naval War College over a century ago: messages that are fed to a staff are delayed or corrupted by the controllers. The strategic game rules of 1905 provide guidance on the use of telegraphic messages and cable cutting and on signalling by wireless, lights, and semaphore (under "Miscellaneous").
Communications (networks, latency, and error rates)
Communications is a critical aspect of modern warfare. To ensure communications is appropriately represented in a game, some form of simulation is often used. Such simulation can inflict delays and message corruption on players. As with other forms of simulation supporting war games, communications simulation must appropriately reflect the real world.
For voice radio, some communications simulation can introduce line-of-sight interruption or static from atmospheric phenomena. For computer-to-computer communications, a simulation may inflict latency due to contention from other users, or corruption of packets. If appropriate, various aspects of electronic warfare may be overlaid on the communications network.
In this section, logistics is decomposed into two aspects. Logistics in terms of supplies that may be carried on various platforms, giving them some autonomy from external logistics support. This will be called "micro-logistics". The other aspect is the network of logistics support needed to maintain forces over the longer term, when on-board resources have been expended. This second aspect is often overlooked in war games, particularly if they are of short duration. In modern warfare, most platforms are self-sustaining for some duration, typically for a number of days.
Micro-logistics (on board support). Most platforms can sustain themselves for a few days. A single soldier will generally carry ammunition, food, water, and medical supplies for short-duration missions. Ground vehicles may carry fuel and ammunition loads for their own consumption, and other supplies that can provide support for crew and passengers beyond what they would carry for themselves. Ships generally have on-board supplies for several days of self-sustained operations. Aircraft, depending on type and mission, may have some reserves of fuel and ammunition for contingencies, although they usually have to plug into some logistics support at the end of each mission.
Macro-logistics (external replenishment, resupply). Periodically all platforms -- from individual solders to vehicles, ships, and aircraft -- need to draw on external sources for logistics support. Appropriate rules are needed for this and there should be considerable doctrine and staff planning data available to develop these.
It is generally agreed that the better a unit is trained the better it will perform in combat. There is also some expectation that a well-trained unit with inferior equipment can defeat a better equiped unit that is untrained or under-trained. There are procedures laid down to assess whether a unit is properly trained on specified tasks.
At the joint level and within the services a task list approach has been adopted for determining training requirements and assessing the success of a training plan. A series of mission essential tasks are specified and from this a unit will determine the training it needs to meet a standard of performance for each task. In an assessment phase, the ability of a unit to perform as required (measures of performance or MOPs). The Joint Training System and the Joint Mission Essential Task List (JMETL) provide a much more detailed description of the system and the process. As an example, the Army has a parallel as outlined in the Army Universal Task List, ADRP 1-03. The other services have adopted this approach as well.
While the task-list approach, with accompanying measures of performance, provides a means of determining training level in a highly quantified way, it does not provide a means of determining relative levels of training for wargame rules.
Morale is widely treated as an intangible factor in combat forces. Generally units with high morale are expected to be more combat capable, given all other factors are equal, than units that have low morale. But it remains debatable how morale can be "traded off" against other factors like equipment or training.
Elite units, with famously high morale, are expected to have highly capable modern equipment and have undergone considerable intensive training. Such characteristics seem to be highly correlated. It is rare to find units with high morale who are poorly trained and have shoddy equipment. So it is difficult to find data where morale has been traded for superior equipment or more extensive training, or where well equipped and well trained troops have low morale. Although when a well equipped and well trained force fails, it may be put down to poor morale. The point is that it is hard in wargaming rules to provide uncontentious procedures for assessing the contribution of morale to the outcome of an engagement.
Chemical-biological incidents and responses
The physical aspects of many chemical incidents can be modelled, e.g., the dispersal of a cloud of chemical agents. Similarly the consequence of a given dosage of familiar in terms of physiological impact on a human body. Unfortunately it is difficult to go beyond this to determine impact on combat results.
Cyber warfare is still an immature area, at least in terms of rules for wargames. In particular determining the correspondence between effectiveness in areas like misinformation and deception and their consequences are not well understood.
Traditionally the effectiveness of nuclear weapons was often determined in terms of a cloud of radioactivity and its affect on downwind populations.
Aggregation and Disaggregation
As indicated above, the characteristics of aggregated units can be difficult to determine. In simplistic terms, we might assume that most of the performance of a soldier as rifleman are largely determined by physics, e.g., the ability to put rounds on target. But as popularized by S.L.A. Marshall in Men Against Fire, many soldiers in a unit may never fire their weapons. Marshall's work remains controversial, but the point remains valid in larger units, the physics of engagements may be dominated by psychology.
When some force has some combat history, this can be used to determine effectiveness. Even if a specific unit lacks historical data on performance, some assumptions can be made that the unit is similar to others, e.g., of the same strength, with the same equipment, provided with the same training, with leadership of a similar quality. With some knowledge of the unit is question, some adjustment could me made for, say stronger or weaker leadership.
However, many OR studies are conducted on units that lack any historical context, e.g., dealing with equipment that is still in prototype, or that may be no more than a concept. For such studies, an assumption is that a unit will be evaluated with current equipment and with the future equipment -- all else will be held constant: morale, level of training, quality of leadership, and so on. This may be the best that can be done, but may be inadequate in many ways, for example a unit with new equipment may find innovative ways to use it that then affects its morale.
To have extensive and authoritative rules to handle all situations mentioned would be a daunting task. In fact all available time in a study could be drawn into a vortex of improving the rules... with little or no time left to play the games. Thus we will often have abbreviated rules in certain areas, with more refined rules for specific areas of interest. This is a widely used expedient, and justified up to a point by the need to be productive. Nevertheless, study teams need to be internally honest about their abbreviated rules and the extent to which they may bias results.
Rules for Scoring
Although scoring (measures of success) are not rules in the sense they constraint what players do, in many games the scoring procedures are given to players as part of the rule book. Some widely used scoring procedures are provided below. Sometimes a unique set of scoring criteria may be used.
Games that have less of a focus on combat results may have tailored scoring systems. For example, a game dealing with logistics might incorporate measures of supply levels for a player's units, e.g., units that fall below a specified level could result in a deduction of points. Or a game focusing on intelligence, surveillance, and reconnaissance might have levels of situational awareness of the command staff as a scoring criteria. Or a game focused on the cyber realm might have some aspect of computer security as a scoring measure. For specialized games like these unique scoring procedures may have to be developed, and will not be covered here.
The scoring procedures below are typical of a combat-oriented game.
Before the game starts, victory conditions are set. These will be used to evaluation the state at the conclusion of the game. These can be shared with players, but they may not be. The victory conditions may include control of vital terrain, countering the enemy's plan, or inflicting casualties on that enemy. Some additional victory conditions (usually "subtracted points") may include casualties due to friendly fire or collateral damage to the civilian population.
Note that a player may be given a mission, but not told of the victory conditions. One reason might be to ensure that the player stays focused on the mission, and that the player is not unduly influenced simply to gain "victory points".
Wins and Losses
At the conclusions of a game, players may be presented with a scoreboard, typically giving wins and losses. These may be measured by numbers of personnel casualties, but may include platforms. It may be a useful shorthand, but can contain
Gains and Losses of Terrain or Geographic Objectives
War games are frequently conducted to see if a player can seize some vital terrain, and how they manage this. Thus points may be added or deducted depending on who controls what terrain at the game's conclusion. While sometimes useful, it can lead to heated debates over exactly what "control of terrain" means; sometimes this will be clear, but it can be ambiguous.
A Pyrrhic victory are rarely desirable as a game result. Usually a game reflects only a small number of operations within a larger campaign. If friendly forces have secured victory, but at the cost of insufficient forces to continue this should affect how the game result is scored. The adequacy of remaining forces is often contentious as it depends on context of for future operations: if condictions are expected to be relatively benign, fewer remaining forces would be required.
Casualties - Personnel
In many wargames, casualties counts are used to measure results. A widespread assumption in this method is that one casualty has the same value as another. Indeed, to make the assumption that each casualty has a unique value begs the question of how to determine that value. Then there are additional complications to the question, for example, how the value will change over time. Little wonder that simpler scoring techniques are preferred where casualties are counted on the basis of equality.
Casualties - Equipment
As with personnel, the simplistic approach of counting equipment casualties is highly contentious. Is the loss of a super carrier of equivalent value (or penalty) as the loss of a destroyer, or is are lost value of a C-130 and a F-15 the same?
If a platform is carrying personnel, what is the lost value of these passengers when the carrier is lost or damaged? What if the personnel can exit the damaged carrier and a portion is still combat effective?
Quantitative and Qualitative Scoring
In other forms of games, think the "Olympics", there are two broad categories of scoring methods. For most of the scoring methods mentioned above, results can be measured by counting on some scale, e.g., numbers of casualties or time required to seize an objective. In that sense they are counterparts to game results by number of goals scored or fastest runner over a given distance. In scoring war games, there are also scores based on judgement, as is done in diving or figure skating competitions. As with such sports a group of qualified judges may give point scores for observed behavior which may be combined into an aggregate score. The judges of military performance may be given some guidance to disaggregate the game activity, e.g., using task lists to break an overall performance into components. Then each task can be scored and these can be aggregated up for an overall score. As with sports events this can reduce the debate over "winners and losers".
Correlation and Contradiction in Scoring
Typically a number of scoring methods will be used in a given game. Many of these will be correlated, or at least expected to be correlated. For example, a player may be scored on the number of enemy vehicles detected and the number killed. There are several ways these can be expected to be correlated: "if you can detect more enemy, you can kill more enemy". Some might argue that scoring on two measures that are expected to be correlated is redundant, and perhaps wasteful of data collection resources.
Another interesting aspect of scoring is when contradictions appear, a commander may achieve mission success, but with far more casualties than the opponent. For an example of the difficulty in scoring a battle with contradictory results, look at the Battle of the Wilderness from the Civil War. Historians widely judge the Wilderness as a draw. However, it could be called a tactical victory for Lee, but a strategic victory for Grant. The Confederate army inflicted heavy numerical casualties on the Union army. But, in terms of a percentage of the Union forces they were smaller than the percentage of casualties suffered by Lee's smaller army. Furthermore Lee, unlike Grant, would have few opportunities to replace losses. So we have contradictory scoring for this battle, but the very contradictions give a much richer understanding.
Tension Over Scoring
War game players tend to be highly competitive, so scoring results where there are winners and loosers can be fraught with issues, and lead to disputes.