Sunday, November 18, 2012

Scenario Design Notes: Delay on Tiger Route (Combat Mission: Battle for Normandy - Commonwealth Forces)

TWC Delay on Tiger Route was uploaded to the Repository on 6 November 2012; this author was also the scenario designer. There were limited Designer's Notes appended to the scenario file. For those interested, a more detailed description of the genesis of this scenario is offered for review and, if desired, further discussion below.


The current evolution of the Combat Mission game engine favours smaller scale battles, and appeals by at least some in public venues, such as the official game forum, for small (i.e. company-strength or smaller) forces have been conspicuous. The author's interest has always been with historical situations (as opposed to obviously fictional engagements drawn up from whole cloth). 

There is a tradition among Combat Mission scenario designers in pushing the boundaries of what is available in the editor, to depict actions strictly outside the historical bounds set out by the program. For that reason, research into small-unit engagements taking place during Operation MARKET-GARDEN in September 1944 have been of interest to the author. Equipment, terrain, weather and order of battle information is adequately represented by that which is present in the editor, and scenarios set in that time-frame will hopefully whet the appetite for the promised official offering currently - it is said - under development.


As the author discussed in detail in another venue1, there is some utility in reviewing the work of others before embarking on one's own design work. Not only is it a good idea to check on scenarios done for the same game/title to prevent duplication (though nothing says that multiple scenarios depicting the same action can't be widely different in design yet equally entertaining), but looking at scenarios in other game systems can also yield dividends as far as suggesting scenario design ideas, from basic idea inspiration to more detailed data such as force composition or suggested victory conditions.

Such was the case here. The scenario Delayed on Tiger Route (note the slight difference in the first word) was published by a third party publisher2, for the Advanced Squad Leader game system in 1996, accompanied by detailed designer's notes in the accompanying magazine.


As with most ASL "conversions", major design changes had to be made to get this to work properly in Combat Mission.


The most notable change was terrain; the wide open spaces of the Squad Leader boards are geared for a board game scaled at 40 metres per hex and contain large tracts of open ground. The boards are generic in nature and "woods" features are considered impenetrable at ranges past 40 metres, by either weapons or line of sight - though a type of "light woods" similar to the foliage in CM:BN is present in the form of "orchard" terrain. Line of sight is merely "hindered" through this terrain and represents less dense concentrations of trees.

The ASL map layout is featured at the ASL Scenario Archive (linked above) and appears as follows:

Michael Faulkner modified the "stock" ASL maps heavily (in addition to careful selection from among the 40+ extant geomorphic maps) to approximate the battlefield, suggesting he had done his homework on the actual terrain. Among the modifications were the removal of Level 1 hills, and addition of five overlays to increase the amount of buildings and woods hexes.

A modern Google Earth map of the battle zone, coupled with period photos and descriptions from a historical blog3, suggested a lay of the land quite close to what the ASL maps portrayed. The exact spot described in the historical snippet was only surmised; a thorough search of unit war diaries from archival sources, or even a better search of second-hand accounts in histories may have turned up better data, but the author was satisfied that a representative sample of terrain was found that would produce a workable scenario. 

Google View
 There were several key elements key to the terrain that needed to be captured on the map:
  1. The main road to Oosterbeek (actually the Heelsum-Arnhem road), which British forces were attempting to travel down, the main purpose of their presence in the area,
  2. A "side road", as mentioned in the source, from which opposing German forces were able to launch an attack,
  3. Woods, part of the forested area west of Oosterbeek conspicuous on period maps and photos,
  4. Fences; in actuality four-foot chain-link fences, mentioned as having influenced ASL scenario designer Faulkner's design choices (specifically, forbidding the use by players of a rule known as 'infantry bypass movement', restricting the mobility of infantry),
  5. Limited elevation changes/contour, consistent with the unique nature of the Netherlands.
Delay on Tiger Route map, looking towards the north-east

Other clues to the terrain were garnered from the book Retake Arnhem Bridge, which also includes a full-colour reproduction of a wartime 1:50,000 contour and terrain map of the Arnhem area.

Building the map was relatively straight-forward; the desire from the start was to permit interesting LOS combinations diagonally across the map, and so taller trees with limited underbrush were selected for the most part.

Wire fences were used to simulated the chain-link fences mentioned by Faulkner (and visible in contemporary photos, such as that below:)

On the road to Arnhem, September 1944. Note the chain link fence.

Forces appropriate to the map size were an obvious concern, part of the balancing act of any design where time/forces/victory conditions have to be coordinated to provide the player with something workable. As stated in the introduction, there is a perception, at least among some, that the new CM game engine is at its best in depicting smaller scale actions. The source ASL scenario was notable for only pitting 3.5 squad-equivalents against 6. 

The command, control and leadership models of CM purport to be more sophisticated than ASL's more primitive modelling, so a straight-across transfer of forces was never contemplated. The flexibility of options in the editor, however permitted the variability of the German order of battle to be better portrayed. The forces present in the actual engagement consisted of a Panzer Grenadier Training and Replacement Battalion. To reflect this, wildly varying Motivation, Fitness, and Experience levels were selected. 

Faulkner's design included two platoons of British paratroopers, and the original CM scenario featured this as well, with a more homogenous set of characteristics, selected from the upper range of options. While the 1st Airborne Division was a well-trained formation, it was relatively inexperienced, despite the earlier deployment of some of its component formations to North Africa, Sicily, etc. Nonetheless, in order that the relatively brittle infantry might be able to use the light anti-tank weaponry on which the scenario might hinge, higher than normal experience and motivation levels were granted as a balancing measure.

Victory Conditions

The most difficult part of getting a Combat Mission scenario design playable is working out a set of victory conditions (in the CM editor, this is a complex combination of "Parameters", "Terrain Objectives", "Unit Objectives" for each side). The second generation Combat Mission game engine has increased in sophistication as far as the types of interwoven factors that decide victory or defeat, though being hard-coded, the designer is still constrained to operate within those parameters.

Again, the designer could not simply ape what was done in the ASL scenario, given the more flexible VC of that system (permissible because of the manual nature of the system). Faulkner's scenario granted points for exiting British forces of the eastern side of the map - something the CM allows for - but adds or subtracts from this point total based on the number of forces the German elects to also withdraw from the map (simulating the strategic necessity to redeploy to meet other threats). While CM does allow the scenario designer to alter basic victory point totals with the addition of "bonus" points, they are not conditional - at least, not in the current iteration of the game engine. One hopes this might be considered for future developments.

Another consideration when designing "exit" scenarios is that units marked for exit must exit or the points awarded for their exit are lost. This is different than in games, such as ASL, where the player is not penalized for failure to exit, other than not receiving the points (i.e. units not exited count as zero, not a negative number as in CM). For that reason, a bonus of 100 points is assigned to the British player to offset an estimated "acceptable" loss of units in a typical scenario. This seemed to work out well in playtesting. Given a choice, however, another suggested change to the engine would be to give the designer the option between the two models of handling points for non-exiting units (i.e. either deducting their value from the point total, or permiting them to remain on map without penalty).


Faulkner describes his ASL scenario as "a short, fast paced scenario that forces the British player (to) take some chances, the German player to be dogged in his defense, and for both players to use every advantage their nationality gives them." In ASL, nationality factors weigh more heavily than in CM, where nationality is not explicity modelled (British troops in ASL are immune to a "Cowering" rule, for example, where "doubles" on the dice reduces firepower, for just one example). Otherwise, in playtest, the CM scenario played rather quickly, given the small area, and the conspicuousness of key weapons systems means that the game can be decided quickly if not careful or a lucky hit is achieved. But, both sides have the tools to win the scenario if handled properly.

In reality, the Germans hit quickly and withdrew in a hurry, taking prisoners then pulling back down the same side road that they struck from. This was the thrust of the ASL design. Many ASL designs came down, in my opinion, to factor counting and last-turn mathematics, which are hard to replicate in CM, and perhaps rightfully so. It was for that reason that the VC permitted Geman exit points to count against British exit points in the original design. Since the CM scenario was being designed primarily from the British perspective, it was felt there was little reason to include this option for the Germans, and the VC didn't permit this kind of conditional VC in any event.

My Question To You

Any feedback on the scenario is welcome, though I'd be most interested in your thoughts on Victory Conditions, whether in CM or tactical games in general, and the kinds of additional parameters or improvements (or deletions) you would like to see. What works well, what would you like to see more of?

  1. Scenario Designer's Handbook, pp. XXX -XXX
  2. Schwerpunkt, issue 1, 1996 Scenario Designer:Michael Faulkner