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MORS Special Meeting on Gaming

Background for the meeting in Fairfax, Virginia, 29 September to 1 October 2015.

Rule Areas

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 the rules. To provide 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. 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 at 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. For play above lower levels of tactical interaction, some aggregation will be necessary, say to determine what happens when two divisions confront each other. 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 or for proposed units used in developing or testing concepts for the future. Since they have no historical record, representing the performance requires prediction. Giving these units systems incorporating advanced technology such units may appear to be on a route to improved performance, but there may be offsetting phenomena. For example, personnel in such units might find their hi-tech solutions are more fragile than systems that have proven performance -- the systems may have poorer operational availability, or require more maintenance or training. The leaders may be challenged to find ways to expoit the future technology. A consequence may be that units that have

Environment (terrain, weather, visibility, obstructions)

Map of Normandy 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 for players. The 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 abati 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.

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, 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.

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.


Apart from the units that are available when a game begins, others may be introduced as the game proceeds. 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 very close to the front are susceptable to being overrun, workshops cannot repair tanks when on the move to stay close to supported units, a lack of tank transporters may mean that operational tanks are available but not in the right location.

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.

Medical support

Personnel casualties are often reflected rather superficially -- they are simply counted and reported. However, casualties can often have a considerable impact on decision making during a game, and in representing results. 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 merely recovery injured troops or downed aircrew, more resources may be needed for medical treatment and evacuation. Field hospitals then require protection from 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 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 "how to set the needle on the dial". Compelling arguments have been made that elite units (US Rangers, 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 illusive.

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.

Decision making

Command and Control (team cohesion, situation awareness)

Communications (networks, latency, and error rates)


Micro-logistics (on board support)

Macro-logistics (external replenishment, resupply)


Medical Support


Special Rules

Chemical-Biological incidents and responses

Cyber warfare

Nuclear weapons

Rule-associated Procedures

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.

Historical Context

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.

Abbreviated Rules

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.

Mission Accomplished

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.

Retained Effectiveness

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.

Rules in Games of the Past

The Naval War Game, circa 1905

The US Naval War College provides a copy of rules used in naval war games in 1901, 1902, and 1905. Of these the rules in the 1905 edition are the best developed. A look at these show many areas are covered: speed and firepower of ships, logistics of replenishment, command and communications (delays in using signal flags and telegraph signals). For the era (over a century ago), these rules may surprise in their completeness.

Hobby Games, circa 1980

From about 1960, for three decades Avalon Hill and SPI dominated hobby mapboard-based wargaming. Over this period they provided many innovations to the gaming community.

Two innovations of particular value were (1) the hex overprinting of a map board (shown here) and (2) a template for manual rules.

Until SPI introduced the template, the format for rules in a new game was left to the whim of the author. And without a template as a checklist, a budding author could miss critical points when designing the game.

After published many war games, James F Dunnigan, founder of SPI, developed a template for rules. SPI published these as guide for potential game authors. Dunnigan provides the template in the form of rules for a sample game in the Wargames Handbook.

Janus: Land Combat Simulation for Professionals

The Janus wargame environment was originally developed by the Lawrence Livermore National Laboratory (LLNL). For many years, the US Army and LLNL developed paralled versions of the Janus system. Source code was provided to many US allies, and they often developed databases of their own, or modified source code to suit local situations.

Janus was the precursor for several more recent simulation packages for land combat, e.g., TacOps, VBS, and OneSAF. It is inappropriate to recommend any of these combat simulations here; the suitability of any such product depends on the application, so an assessment of available products is up to the Study Team for any particular project.

Steel Panthers: Poor-man's Land Combat Simulation

Steel Panthers is a computer-based hobby game originally developed in the 1990s. Due to changes in the ownership of the intellectual property, copies of this game of a variant Steel Panthers - Main Battle Tank (or WinSPMBT) are available as a free download. An enhanced version, with terrain, equipment, and scenario editing capability, is available at nominal cost. For those new to gaming and with a mandate to develop land-based games, may find this game provides a low-cost option for introducing many aspects of game design and computer-based rules. The game has considerable sophistication to determine movement rates, no-go areas, and lethality.

The game was developed from an earlier variant meant to provide hobby gamers with the ability to re-fight armored and mechanized battles from World War II. Steel Panthers - Main Battle Tank is intended to represent modern land-based operationS circa 1946-2020 at brigade level and below. Apart from representing armour, mechanized, and infantry units, it has the capability to represent fixed-wing close air support, attack helicopters, amphibious operations, and logistical resupply.

This game is not likely to be suitable for any deep study of tactics or equipment, but it should provide a valuable educational tool for anyone who needs to develop an understanding of how war game procedures can be captured in a computer program.

Command: Modern Air/Naval Operations

A "shrink wrapped" game for air and naval operations that is equivalent to Steel Panthers is Command. As for Steel Panthers, this game is not recommended for professional game-based studies. However, it may provide a novice in computer-based gaming with a useful and inexpensive introduction to many techniques that may be applied in other models or simulations. Command: Modern Air/Naval Operations is available at a nominal cost; there are no free downloads however.

The game rules provide for planes and ships to be played at the platform level and ground units down to the size of a platoon. Platforms are provided with a wide range of weapons and sensors. This game from the hobby community may also surprise in its sophistication: it includes representation of termal layers in the ocean to allow submarines to exploit such phenomena to evade sonar detection.

Other Simulators