"Loopy" Wargame Design

I found David's 27 June piece on Principles, Models, and Algorithms interesting and figured the post deserved more than I could produce in a short comment to his post directly.  After some thought, I tackle David's essay.

To briefly summarize David's essay, he argues that rules can be understood at three levels (or layers): principles, models, and algorithms.  Principles are broad goals that require judgment and may be ill-defined or vague.  Models are the underlying ways in which we try to understand reality and quantify those perceptions into workable solutions.  Algorithms are the mechanisms used to resolve and adjudicate game actions without any bias or judgment.  David suggests that this process carries a definite hierarchy with Principles at the top followed by Models and finally Algorithms.

David's perspective on algorithms (rule mechanisms) is that they are useful since discrete rules can be applied consistently by anyone.  That is, if the rules are clear and without ambiguity!  A potential downside pops up when these algorithms mask the principles and models underlying them.

David's hierarchical way of considering rules and scenario writing is a helpful approach.  The distinction between principle, model, and algorithms is useful.  My experience in evaluating ruleset design illustrates that many of the arguments about wargame rules come from confusing these levels or from expecting one layer to do the work of another.

To respond to the post, I first relabel David's levels to terms that carry more meaning to me.  "Objective" replaces "Principle" and "Mechanism" replaces "Algorithm."  "Model" remains the same.  I tend to think of these levels not as hierarchical, one-way progressions but as layers that interact with one another.  When a rules mechanism exposes a flaw in a model, the objective may need to be re-examined.  In practice, designers move back and forth between each of these levels in a loop as shown in the diagram below.

In scenario (and rules) design, the idea that objectives sit at a higher level of abstraction than mechanisms feels exactly right.  The aim of a game is not always simply to defeat the enemy.  Once objectives shift to delay, escort, screen, or hold key terrain pieces, the whole character of the game changes.  Objectives should not be vague or ambiguous.  In a sense, objectives help to shape and classify the historical problem we are trying to represent on the table.  Victory conditions, laid out as an objective, tend to shape player behavior more than mechanisms do.

The idea of a model is also useful, but some clarification is warranted.  A model in wargaming is not only conceptual but takes the role of creating a selective abstraction of causation.  As a designer, we make choices.  In other words, a model tells us what we think matters in a given historical situation.  That seems especially important in wargaming, where two rulesets may look similar on the surface but actually rely on different assumptions about morale, firepower, cohesion, or command.  There are different types of models in wargame design as well.  Models can include physical models (ranges, formations, movement rates, weapons effects), behavioral models (morale, command friction), and perceptual models (fog of war, limited intelligence).  Different combinations of models or different implementations explain why two rulesets with the same, core mechanisms can feel very different.  

On mechanisms removing judgment altogether, I find this not the case.  Mechanisms certainly channel responses, which is valuable, but they do not eliminate judgment from the game as a whole.  Rather than eliminating judgment, mechanisms relocate it.  Players still exercise judgment in movement, target selection, risk-taking, timing, and so forth. Perhaps a better point is that mechanisms confine judgment by removing arbitrary rulings.  Mechanisms allow for a more explicit and repeatable structure.

In the end, the most valuable part of David's essay is that it reminds us to ask not only whether a rule works, but why it works.  A game may have clean mechanisms but still fail to express the historical problem it is trying to represent. Conversely, a simple mechanism can work quite well if it is supported by a sound model and a clear objective. A looping design and development structure helps to focus the interaction between the three levels of objective, model, and mechanism.

Thoughts on Montebello

All is quiet on the battlefield of Montebello.  In fact, the table has been dormant for the past two weeks with no activity at all.  Well, besides figures and sorting projects piling up on it.  That will soon change, though.  Richard has agreed to a rematch from our earlier game (see No Duke of Montebello).  For the next episode, we will swap sides and refight the battle from a different perspective.

Birdseye view of battlefield.

Before that game hits the table, time for a little reflection on the battle, its historical counterpart, and the rules.

Looking back at the battle report linked above, the game offered a tense battle as the French Army under Lannes scraped out a dramatic last‑minute victory.

Game Recap

Against the odds, Watrin’s French division assaults O’Reilly’s advanced position at Rivalta through the tall rye fields surrounding the village.  Initial attacks are repulsed, but repeated assaults eventually break O’Reilly after brutal fighting south and north of the village.  The Austrian jaegers are finally compelled to give up their defense of Rivalta.  As the French push on to the west, Vogelsang brings up his reinforcements to Cascina il Giardina while Schellenberg reaches Montebello.  Ott tries to form a defensive line as the Austrian army falls back toward Casteggio.

Attack on Rivalta.

To the south of Rivalta, the 28th Line ejects Austrians from Cascina il Giardina after repeated attempts to take the strongpoint.  Lannes then leads his hussars in a devastating charge that destroys an Austrian infantry battalion and overruns a retiring battery.  Unfortunately, Lannes falls in the confusion.  The Austrians are not done yet.​

Lannes leads the charge!

Austrian dragoons countercharge and scatter the depleted French cavalry.  Seemingly out of nowhere, a third hussar unit strikes unsupported Austrian infantry.  With the combat raging and both formations on the brink of collapse, the Austrian infantry are scattered and Vogelsang's Division breaks.  With O'Reilly and Vogelsang broken, Ott is compelled to quit the field.  Lannes gains victory with a razor-thin margin.  It could have tipped the other way.

The destruction of Vogelsang.

Post-Game Thoughts

Montebello offers challenges to both players and scenario design.  With both armies arriving piecemeal and a tight timeline to clear the highway, the French are forced into attacking at unfavorable odds.  When Watrin first attacks Rivalta, the defenders hold about a two-to-one advantage.  As the fighting builds with fresh reinforcements reaching the field, the battle emphasizes a measurable quality‑versus‑quantity dynamic as well as trading space for time.  A situation that Ott and Lannes, themselves, faced.  Players faced the same conundrum.  That is, how best to utilize the forces at hand.

With Lannes' qualitative advantage and ability to pick and choose the place and timing of attacks, as Ott, I fell into a similar trap.  When Watrin's initial attacks were repulsed, O'Reilly made the decision to stand and fight at Rivalta.  Only as more French reached the battlefield did he realize his mistake.  By the time Vogelsang approached from the west, it was too late for O'Reilly.  His formation was wrecked and in retreat everywhere.  Vogelsang tried to bring his division up and hold Cascina il Giardina but that stronghold could not be held after repeated attacks.  In the vicious fighting around that stronghold, Vogelsang's Division was wrecked.  With two of his three formations broken, Ott was forced to yield the field of battle.

The flow of the tabletop battle broadly followed the historical battle.  While the fighting may have played out with variation, the end result was the same.  That is, Ott's command was forced to retire from Montebello and head back to Alessandria to lick its wounds.  Five days later fighting would resume at Marengo.

Now, scenario design and often rules' writing remain as works-in-progress.  This refight offers similar thoughts on amending scenario details.  Having realized the historical result in the first outing, how much really needs to be tweaked?  While Victor/Chamberlhac played a role in turning the battle historically, in this playing Chamberlhac barely reached the field.  Same can be said for Schellenberg on the Austrian side.  

Schellenberg arrives.

While providing a good-sized game for two players, Montebello presents a more difficult path for multiplayer games since reinforcements arrive throughout the game.  This might lead to players not getting into the action right away.  Meeting engagements offer unique challenges for multiplayer games.  To steer the game toward this end, the next refight will see game duration lengthened from 8+ turns to 10+ turns while unit arrival times will see some compression.  The caveat, here, is that reinforcement compression may alter the already finely balanced arrivals to match the historical situation.  Do you come down on the side of history or player engagement?  Should arrival times be adjusted based upon the number of players present?  That is, keep historical times in a two or three player game but compress arrivals for larger multiplayer games so that everyone is involved within a turn or two?

Before I take command of the French Army in the next game, there is much to consider.

Grasping for Your Potential (Charge)

When hosting a game using Basic Impetvs, one of the rules that regularly causes confusion is the rule on Potential Charge against skirmishers and light cavalry.  Part of the problem could be in my explanation!  I will try to explain...

What is a Potential Charge?

Before a charging unit strikes out toward a skirmisher or light cavalry target, the charging units announces whether it will attempt a "Normal Charge" or "Potential Charge".  The rules state that,

5.8.1 Charging troops that can evade
Units that want to charge CL or S can declare to move up to the
position where CL or S are (so called “Potential Charge”). The
Non-active Player then chooses to evade or not. If he evades,
the Unit of the Active Player must move at least to a position
where contact was possible without evasion. As this is not a
charge, the Unit, if armed with missile weapons, can also fire.
If the Movement Charge Bonus (5.6.1) is used and the contact
was avoided by an Evasion, the charging Unit ends in Disorder.

In practical terms, what does this mean?

Skirmisher is target of charge.

A Potential Charge lets a player declare a move that could end in contact forcing the target to choose and resolve its evade reaction before the charging unit commits to a full charge.  If the movement actually reaches the target through either a failed evasion test or a short evade, the Potential Charge becomes a normal charge and melee proceeds.  If evasion is successful, the charging unit simply completes a normal move without the possibility of entering into melee.

Why Use a Potential Charge?

The decision between choosing a Normal vs Potential Charge is not always straightforward.  There are several situations where a Potential Charge might be useful.  Three such situations are outlined below. 

Forcing Enemy Reactions
A Potential Charge compels a skirmisher or light cavalry target to resolve an evasion attempt or stand and accept the charge.  This forces the defender into a dilemma.  Evading might open flanks to other units while standing could expose the target to a full charge.  Often (although not guaranteed) skirmishers or light troops successfully evade resulting in a Potential Charge reverting to a normal move.  If driven off through a successful evasion, the change to a Normal move may offer favorable positioning without the risk of melee and/or pursuit.

Enabling Feints and Pressure
By declaring a Potential Charge, aggressive units like cavalry can threaten multiple targets, drawing out evasive maneuvers to create gaps in the enemy line for a decisive follow-up charge by another unit.  Successful evasion can leave retiring units potentially out of position allowing the feinting unit to pivot and support elsewhere during the same activation.

Improving Position
The mechanism allows control over movement endpoints.  If contact fails due to evasion, then the charging unit completes a normal move to an optimal spot.  Potential Charge control avoids overcommitment of a full (Normal) charge into empty space.  The ability to shoot and maneuver is preserved.  The advantage of this result is that Zones of Control (ZOC) pressure can be maintained without immediate melee.  Over several turns and constant threats, an enemy can be worn down in such fashion.

In larger battles, Potential Charges support coordinated tactics, such as using fast skirmishers to trigger reactions while heavy units reposition for a real assault.  Potential Charges provide tactical advantages by allowing the charging player to force the enemy to commit to a reaction before fully expending the unit's movement.  in this way, information and positioning is gained without risking a failed commitment.  This mechanism enables subtle maneuvers like feints to disrupt enemy plans, waste their activations, or set up subsequent real charges elsewhere on the battlefield.

When to Use

Potential Charge.  Declare a Potential Charge against fast, evasive troops where successful evasion would leave your unit overextended or in a poor position.  This mechanism lets the target resolve its evasion first, potentially turning your action into a normal move with options for follow-up shooting or repositioning.  This tactic works well when charging through potential obstacles or when multiple threats exist, enabling feints that disrupt enemy cohesion without wasting your unit's activation on a guaranteed miss.  This approach is ideal for light or mobile units probing for weaknesses in the line, preserving their flexibility for later turns.

Normal Charge.  Commit to a normal charge against stationary or slow-moving enemies, such as heavy foot in formation or against units where the risk of evasion is low and the distance can be reliably closed to trigger melee with full impetus dice.  Normal Charge is preferable when the attacking unit has superior speed or the target lacks reasonable evasion capabilities.  This ensures the charge bonus applies fully and pursuit opportunities arise if victorious.  In aggressive setups like cavalry against exposed flanks, this direct approach maximizes shock value without the hesitation of potential outcomes.

Key Differences
The Potential Charge provides information and safety against reactive foes but may limit the attacker's immediate combat impact if contact fails.  A Normal Charge, on the other hand, requires precise measurement and commitment for decisive results but risks failure if the target slips away.  Consider the attacker's impetus rating and the enemy's disorder status.  Potential Charge is tactically superior to a Normal Charge when facing evasive enemy units as it forces enemy commitment to evasion before the attacker's full movement is exhausted.  This contrasts with the Normal Charge's full commitment, which maximizes impetus bonuses but risks overextension against slippery foes.

Clear as mud?  I guess we will see in the next game!

Challenges to an "Authentic" Medieval Wargame

Back in October of last year, I attended one of Georgetown University Wargame Society's ongoing lecture series.  On tap for the October lecture was Robert W. Jones' talk on The Challenges and Pitfalls of an "Authentic" Medieval Wargame.   Dr. Jones, the author of the Medieval wargame rules Blood and Horse Droppings, brought up a number of interesting topics and points to ponder when creating a set of Medieval rules.  While I had planned on offering up a summary of the discussion much sooner, my motivation to re-address the presentation was triggered by a challenge to bring my yet unblooded Wars of the Roses collection to the gaming table.  With what I want in a Medieval wargame and rules of engagement still in the formative stage, I returned to my notes from Dr. Jones' presentation for inspiration and clarity.

Given the title of the talk, I was not surprised or disappointed in seeing Dr. Jones present a list of challenges and pitfalls to designing a Medieval wargame and how to address those challenges in game design.  The central theme of the lecture should not be foreign to any wargame designer.  That theme focused on the tug-of-war between playability and historical simulation.  Let's briefly reconsider the salient points on what Dr. Jones had to say on the topic of Medieval wargame challenges.

Medieval wargaming, like Ancients wargaming, often encompasses large chronological periods.  Medieval rules can cover nearly a millennium of military history from the fall of the Western Roman Empire to the Great Italian Wars.  Universal rules, using a common game engine, tend to categorize troops according to common criteria across several periods.  Players use the same mechanisms and nomenclature regardless of historical context.  Standardization allows players to switch between periods more readily but at the loss historical specificity over convenience and playability.

Having such breadth in Medieval rules suggests a lack of understanding regarding the technological and tactical evolution present throughout the period.  There is no equivalent descriptive label such as "Horse & Musket" or "Pike & Shot" to describe Medieval warfare's dominant military technologies.

The limited and unreliable historical sources available pose problems as well. Medieval chronicles lack tactical detail, exaggerate numbers, and prioritize political or religious narratives over complete and accurate battle accounting.  Administrative records focus on logistics, not battlefield behavior.  Troop types often reflect national myths ("rash" French knights or "unstoppable" English archers) rather than historical nuance.  Rules often impose 18th/19th-century concepts such as drilled units or hierarchical command onto Medieval armies.  Medieval armies often lacked standardized training and the leadership structure was primarily flat.

Finally, the most significant challenge for medieval wargaming is that historically accurate Medieval battles make for tedious games.  Medieval battles were static and chaotic by modern standards, making them less "fun" as games.  The limited command and control, lack of tactical flexibility, and inability to disengage and redeploy units means Medieval battles involve minimal maneuver once lines are engaged.  Commanders had few tactical decisions once battle was joined since they were often fighting in the front lines.  An historically accurate simulation would essentially line up armies, advance to contact, and watch the clash unfold with little player input.

Are these foreseen challenges to designing a Medieval ruleset correct?  Are there other considerations?  Do answers to these challenges depend upon level of abstraction modeled or the player’s role in the game?  Is designing/developing a "fun" set of Medieval rules even possible given these constraints?  Many reckon it is including Dr. Jones!

With the challenges as seen through Dr. Jones' eyes laid out, next I consider solutions and rules.  Something to dive into another time.

What's In A Name?

After seeing the above book mentioned on Peter's blog (see A New Book...) and listening to the authors' podcasts, I placed an order.  Book arrived quickly and was read just as quickly.  I won't repeat the contents of the book since Peter did that and Table of Contents can be seen on Amazon.

What I do want to discuss is the authors' wrestling with the renaming of the gaming aspect of the hobby that we enjoy.  Many of us likely refer to this hobby as miniatures wargaming or playing a miniatures game.  Really, I lump all facets of the hobby simply into the catch-all, wargaming. 

The authors' take a different tack, however.  They state their rationale for first dismissing the use of tabletop games, then dismissing miniatures games, then dismissing miniatures wargames, before settling onto the term of non-discrete miniatures games. 

The name, non-discrete miniatures game is chosen since the authors argue that,

• Games are not necessarily about war.
• Spatial relationships between miniatures and terrain are crucial.
• Any physical object can be introduced into the game and have meaning in game terms (non-discrete components).
• Movement and positioning are not limited to fixed increments or grid spaces (non-discrete positioning).

Non-discrete is an interesting term to choose and returns me to the days of studying mathematics.  Typically, one sees a bifurcation between discrete and continuous but not between discrete and non-discrete.  I suppose if the term, continuous was utilized as in continuous miniatures game, readers might conclude that we game non-stop!      

Moving on, the authors define these games by their unique spatial characteristics in that,

• Precise physical positioning matters.  That is, movement and placement are analog (and continuous) and not grid-based.
• Players can bring any object to the game table and game systems must accommodate an infinite variability of components.

One example given of discrete movement and figure (marker) placement is the game of Monopoly.  A playing piece can only be in one of the grid spaces on the playing board at any one time and not between two spaces.  In a non-discrete game, movement is governed by a measuring device with a miniature able to move anywhere along that vector and stop anywhere short of the maximum move distance allowed.  This non-discrete movement criterion seems to not only explicitly exclude grid-based games from inclusion into non-discrete miniatures game by definition but implicitly as well with the continuous nature of measured movement along a vector. 

In later chapters, the authors relax the condition for non-griddedness.  Games having gridded movement or zoned movement may fit into the structure of building a non-discrete miniatures game as long as the focus on the design remains on the spatial relationships within the game and the infinite variety of components.  Given that discrete positioning and movement criteria are later relaxed, the grid vs non-grid distinction should be dropped from the definition altogether.

With the argument for excluding gridded games jettisoned, what remains the focus of non-discrete miniatures gaming?  What remains constant is the reliance upon the external components brought into the game system.

What distinguishes many boxed miniatures games from the non-discrete miniatures games that the authors describe?  The difference is that the former is self-contained with the rules and all of the components necessary for play while the latter is similar to a toolkit with a programmed game engine requiring any number of external inputs provided by the player(s).  These external inputs could include figures, terrain, army lists, dice, measuring devices, etc.

       

Is the classification still between discrete vs non-discrete miniatures games or is a better fitting distinction between endogenous vs exogenous miniatures games?  I suggest that the latter terminology may be a better fit if one agrees with the authors that the deciding attribute is bringing external inputs into the system.  Still, it is all wargaming to me.

There is much more to be pulled from this book of interest to wargamers and wargame designers whether focusing on non-discrete miniatures gaming or not.  I have only brought up the main thesis of Chapter 1!  With so much to consider, I may non-discretely dip back into this text on occasion.

On the Table

Having cleared the table from the last of the Samurai Azukizaka battles (yes, I am now behind two battle reports!), time to head off in a different direction with a different period.  After considering a few options, a request for a return to the Great Italians Wars was suggested.  Sounded good to me.  The last time the collection saw action was back in April and May of this year with a string of five, Battle of Fornovo games with an assortment of player groups.

What to bring to the table this time?

Since I used Verginella's scenario book as a starting point for Fornovo and before that Sanguetta, I grabbed the book and began thumbing through the scenarios looking for a suitable and interesting battle to bring to the table.  Two other requirements were that I needed a battle that fits my collection size and a contest suitable for four players.

After considering the possibilities, I settled upon the 1509 Battle of Agnadello.  While Verginella provides simple maps and an Order of Battle, the book is really a toolkit and jumping off point in my mind.  For me, there is never enough detail on scenario and victory conditions to formulate a viable scenario without a little (often much) tinkering.  

While Agnadello is mentioned in a number of internet searches and included in some of the books in my library, one of the most complete accounts is found in Predonzani and Alberici's The Italian Wars Volume 2.  Great book as are all of the titles in this series.  Recommended.

I also turned to GMT's Arquebus boardgame for inspiration and information.

After considering the sources and my battlefield and collection constraints, I arrive at the battlefield as illustrated below:

Battlefield

Army deployments

While Agnadello is listed as a "Large" scenario, it really stretched the limits of my collection.  I just managed to field the nine pike blocks required.  I always figured that nine was enough.  Not so!  If the optional "what if" scenario of seeing Pitigliano reach the field in support of the Venetians is included, more work needs to be done. 

As the scenario stands, the Venetians are outnumbered but holding favorable ground.  Historically, the Venetians were destroyed in this battle but all is not hopeless.  With ditches and vineyards to negotiate, the French will have a difficult time on the approach.  Compounding the terrain difficulties, the chance of rain adds to the uncertain nature of the outcome.  Perhaps with some luck, the Venetians can effectively run out the clock while remaining on the field of battle?

Like the rain present on the field at Fornovo battle noted above, accounts mention rain on the field at Agnadello too.  Accounts vary on the presence of rain. Some accounts state the rain was present when the battle began. Some state the rain began midway through the battle. Some accounts, including the Predonzani book above, never mention it! When rain is mentioned, it poses a serious obstacle in both movement and negotiating the ditch as the ground softens and the ditches fill with mud.

Scenario design is always a bit of a guessing game with a little trial and error thrown into the mix.  We will see on Monday if the scenario survives first contact.

Niccolo Machiavelli, in his book The Prince, famously commented on the battle's impact, stating that in one day, the Venetians lost what had taken them 800 years to conquer.

Review: Thomas' Wargaming 19th Century Europe - Redux

 Neil Thomas' WARGAMING NINETEENTH CENTURY EUROPE 1815-1878

Given David's recent musings on contemplating embarking upon a Risorgimento project in 6mm and Neil Thomas' Wargaming Nineteenth Century Europe 1815-1878 (see Imperfect Painting), my thoughts returned to this classic work and the rules, themselves.  Tossed into this inspirational mix is Keith's move to resurrect or recycle old posts (see An "Almost" Anniversary Post).  Seems that the pair of posts from David and Keith converged to nudge me in a similar direction.  Call it serendipity.

With their inspirations, I resurrect a post from the very early days of Palouse Wargaming Journal.  Reproduced below is the 29 OCT 2012 post on my overview of Thomas' book.  Hard to believe this review was published a dozen years ago.  At the time, my review garnered a grand total of one comment.

Thomas' Wargaming 19th Century Europe book remains one of my Top 10 all-time wargaming books.  I might even push it into my Top 5.  Even with the passage of a dozen years, my appreciation for this book is unwavering.  While I do not use these rules for my own Risorgimento wargaming, perhaps I should give it a try?  Typically, my adaptation to Fields of Honor is my "go to" choice for gaming the period.  In fact, I tend to use Fields of Honor for many horse and musket periods.

What might be interesting is to offer a side-by side comparison of both rulesets to investigate any similarities and differences.  Will a comparison between the two cause a change in perception of Thomas?  For now, below is the republication of my review of Thomas' book from 2012 (see original post at Review: Thomas' Wargaming 19th Century Europe).

Hope you enjoy this look back down memory lane.  I did.

--- Original Post from 29 OCT 2012 ---    

Having an interest in 19th Century warfare in general and the Second Italian War of Independence in particular, I recently bought Thomas' book.  Wargaming 19th Century Europe is my first Thomas wargaming book so I didn't know what to expect.  Existing reviews are lacking the detail needed to make an informed decision but I plunged ahead anyway on the road to discovery.

Although the book covers a wide span of history (some might argue too large since weapons and tactics evolved throughout this period), Thomas justifies his position by reminding the reader that the mindset of commanders during this period remained practically unchanged.  That is, commanders continued employing Napoleonic tactics over this 60-year span.  This same argument could be made for the American Civil War as well.  

Thomas provides a comprehensive examination from a wargaming perspective.  Thomas breaks the book into a number of manageable chunks.  These components include sections on:

• Historical background
• Design notes
• Wargame rules
• Generic scenarios
• Army lists
• Historical scenarios
• Appendices listing bibliography, scales and figure discussion, and wargame related vendors

The rules, themselves, only take up eight pages and cover,

• Units and Formations
• Basing
• Sequence of Play
• Changes of Formation
• The Charge Sequence
• Movement
• Firing
• Hand-to-Hand Combat
• Morale

The rules' mechanisms lean decidedly towards the simple end of the wargame complexity scale and Thomas defends this approach throughout his design notes chapter (entitled, Nineteenth-Century Wargaming).  Thomas emphasizes the "simple" rules' design approach to allow players to focus on the game rather than the rules.  The rules have no specified time or figure scale. 

All units of the same type are the same size regardless of historical doctrine.  Unit size is,

• Infantry - four bases
• Skirmishers - two bases
• Cavalry and Dragoons - four bases
• Artillery - one base

Basing guidelines are provided but any basing scheme should work as long as both combatants are based similarly.  

One interesting step in the Sequence of Play is that formation change is a separate step and that infantry may not move in line.  The result is that infantry may only charge to contact while in column.  Only infantry and artillery may change formation.

In the Charge Sequence, Thomas provides a matrix for easily determining whether a charging unit may contact a defending unit.  Conditional charges are allowed provided that the charging unit outnumbers the target.  If attacked frontally, defenders may fire at the attacker before hand-to-hand combat is resolved.  

In the Fire Phase, firing units throw a number of dice per stand dependent upon unit type (rate of fire).  Ranges are singular per weapon type with the exception that smoothbore guns have both a short and long range, and skirmishers add 8cm to weapons' range.  Hits are cross-referenced with respect to firing unit and target.  For example, an infantry unit firing in line against an infantry in close order line needs 4-6 on each D6 to score one hit.  Each base may take four hits before removing one base.  Saving throws are allowed for provided the target unit is either in cover (woods or towns) or armed with breechloading weapons.  The rationale for the breechloading saving throw is to model the tendency for breechloading armed troops to "go to ground" when under heavy fire.     

In Hand-to-Hand Combat Phase, each unit totals the number of dice it throws against its opponent with each stand receiving a set number of dice dependent upon the attacking and defending unit types.  Like fire, saving throws are allowed for units in woods or towns.  The side taking the largest number of hits retreats after Hand-to-Hand. 

During the Morale Phase, only three conditions trigger a morale test.  These conditions are:

• Losing a base through fire combat
• Charging cavalry takes fire from defending target
• Losing Hand-to-Hand combat

Notice that in the case of a cavalry charge, the defender does not necessarily have to cause casualties to trigger this morale test.  Thomas argues that the process of taking fire during a cavalry charge was often enough to cause 'extreme' disorder within the charging cavalry's ranks.  Units are rated in five distinct morale classifications.  These are, 

• Fanatic
• Elite
• Average
• Levy
• Rabble

with each classification given a set range of values on 1D6 for passing the morale test.  Fanatics fail only a on a roll of '1' while Rabble fail on any roll other than a '6'.

To me, the most interesting portion of Thomas' book is contained in his design notes in chapter 2.  This chapter allows the reader insight into Thomas' rationale for designing the rules as written.  Some thought provoking ideas are surfaced within and prompts me to consider some of my own gaming designs.  Thomas' rules definitely possess the flavor of classic, Old School wargames as handed down from the pioneers of Featherstone, Grant, Wesencraft, and Morschauser.

Computational Combat Statistics

Well, if there ever was a post title that would cause readers' eyes to gloss over and tempt them to skip a post, today's post might fit the bill. Had I mentioned that this would be an exercise in mathematical simulation, I may have lost everyone.

What am I doing and why?

Motivation

In the first game of Madonna dell'Olmo (see Madonna dell'Olmo), King Emmanuele III automatically holds the initiative on Turn 1.  With Spanish grenadiers defending the redoubt positioned in front of the cathedral, the prospect of storming the position looked daunting.  Given that taking this position is one of the criteria for eventual victory, the cathedral and redoubt represent a key piece of real estate.  With Spanish support nearby, attacking on Turn 1 may offer the best chance at securing the position before the Spanish grenadiers are reinforced.  What the Piedmontese must accomplish is to either destroy the grenadiers or throw them out of Madonna dell'Olmo on Turn 1.  While success may be short-lived, the loss of the Spanish grenadiers and occupation of the cathedral will set back Spanish plans on this wing for at least two turns.  This is valuable time the King could put to good use. 

Turn 1 starting positions.

In last week's game, the King opted to use his first turn initiative to activate other formations and stand pat with Corbeau's Far Left Wing in front of Madonna dell'Olmo.  Is this the only viable strategy?  Consider a few choices of action. 

Options

1. Do nothing.
2. Use first fire volleys with Grenz and attack with the grenadiers.
3. Attack with grenadiers and grenz.  Corbeau does not lead the charge.  
4. Attack with grenadiers and grenz.  Corbeau leads the charge.   

Only one of the grenz regiments and Sardinian grenadiers can reach the redoubt on Turn 1.  Can one of these four scenario options lead to success using the rules in play?  Can players assess intuitively beforehand if any of these options provides a path to success?  Intuitively, it may seem that (4) may offer the best chance of success but will this be enough to dislodge grenadiers in the heavy cover of the redoubt?  Perhaps combining an assault with preparatory volleys is useful?  

Discrete Event Modeling

Now, if these events required only a single computation, getting an answer may be straightforward.  However, there are many events in play both sequentially and simultaneously.  To get a grip on possible solutions, conditional probabilities are involved.  To accomplish this task, discrete event simulations need to be built and executed.  Once built, these combat models will be executed 500,000 times per scenario to create a large sample size from which to draw inferences.

Let's looks at each one.

1. Do nothing.  No computations needed here.

2. Grenz volley followed by grenadier assault.  This scenario requires first a simulation of volley fire and defender morale tests followed by paired simultaneous close combat attacks and morale tests by both attacker and defender. 

The grenz' first fire bonus offsets the heavy cover penalty of the redoubt.  The results demonstrate that grenz first volley fails to score a hit and resulting enemy loss through morale failure about 42% of the time.

Assuming the grenz fail to make a mark against the defenders, then the subsequent assault yields the following result.  That is, the defender is only forced out about 30% of the time.

What if the grenz manage one hit?  Well, then the results change to,

with the chance of defender retreating jumping from 30% to 38%.  Still, prospects for success are not great.

Is this worth the risk especially given the risk to the attacker where "Attacker Retreat" and "Fight On!" results carry losses to the attacker?  A “Retreat” result signifies an actual retreat or unit destruction.  In either result, the unit vacates the hex.

3. Attack with grenadiers and grenz.  Corbeau does not lead the charge.

This scenario sees the Sardinian grenadiers assault the redoubt without any preparatory volley from the grenz but the grenz join in to support the assault.  Corbeau does not join in to lead the attack.  This scenario requires paired simultaneous close combat attacks and morale tests from both attacker and defender.   

These results show, that on average, the defenders will be ejected from the redoubt about 57% of the time.  Again, the attacker suffers losses through failed morale tests about 40% of the time.

4. Attack with grenadiers and grenz.  Corbeau leads the charge.

This scenario sees the Sardinian grenadiers assault the redoubt without any preparatory volley from the grenz.  The grenz join in to support the assault while Corbeau leads the attack.  Like scenario (3), paired simultaneous close combat attacks and morale tests from both attacker and defender are required.

With Corbeau leading a coordinated attack at the head of both grenadiers and grenz yields success in throwing the Spanish grenadiers out nearly 75% of the time.  For me, that is a risk worth taking.  Of course, the attackers will suffer casualties but the price for gaining the redoubt seems not too high. 

For this situation, a coordinated assault with an attached general provides the greatest payoff.  Of course, if Corbeau is lost or the Sardinian grenadiers are badly damaged, holding the position may be difficult unless reinforced quickly.  Still, aggressive action by the King on Turn 1 could set the direction for the entire battle.  

Without tackling the complicated and intertwined computations underlying the game engine, itself, it can be difficult to "guess" which approach is best.  Even with a correct guess, confirmation is valuable. 

What would I do?  Attack straight away with full force.  Your mileage may vary.

Assessing Victory Conditions

In scenario development, victory conditions drive both the narrative and direction of battle.  These criteria often drive player decision-making as well.  When fighting historical battles, victory conditions may be obvious such as "destroy the enemy army" or "take this objective".  For other battles, implementing criteria to fit players snuggly into their historical counterparts' shoes is difficult.  How does scenario design and development restrict game flow in such a way so that players face similar decisions?  I think accomplishing this task is as much art as science.

Why do I bring this up today?

  
Well, I have been preparing to host the 1744 WAS Battle of Madonna dell'Olmo.  The battle is interesting and setting victory conditions complicated.  The Austro-Piedmontese Army under King Emmanuele III lost the battle but secured a strategic victory.

Let me provide a brief background summary from my battle briefing.

Madonna dell'Olmo deployments

Background

After much disagreement in campaign aims, the Gallispan Army (France under Conti and Spain under La Mina) agreed to take the war into Piedmont.  Having crossed the Alps and descending into Piedmont, the Gallipans won some victories on the approach to Cuneo.  Taking Cuneo was crucial in that the city offered a place to spend the winter before the Spring campaign of 1745 began.  Standing in their way was the Piedmontese Army under King Emmanuele III.

The Gallispans laid siege to Cuneo on the night of the 12-13 September.  With Cuneo now besieged, the King must act to relieve the siege.  The King came up with a multi-faceted plan.  His plan focused on drawing the Gallispans into pitched battle in order to send supplies into Cuneo and evacuate wounded.  MG Leutrum was in command of the Cuneo garrison.  He would sortie from the fortress to destroy the enemy’s siege works across the Gesso River when the besiegers took to the field.  While the Gallispans were engaged outside of Cuneo fighting a pitched battle, Bourbon outposts and lines of communication would be attacked.

As long as the Gallispans could be engaged in pitched battle without knowledge of the other goals (and without destroying his own army), the King could snatch a strategic victory without needing to win the pitched battle.  With LOC cut, Cuneo reinforced, and winter approaching, the Gallispan Army would be compelled to break off the siege and retire back into France to winter.  Emmaneule needed to buy time.

Historical Outcome
The battle began around noon with probing attacks upon Madonna dell’Olmo escalating into a pitched battle.  With the battle lines separated by a sunken road over about half of the ground, each commander continued to shift forces toward the center and Madonna dell’Olmo in order to come to grips with the enemy and hopefully break through.  After heavy fighting throughout the afternoon with little headway made, the King called off the attack and retired.  Still, the day’s action allowed the Gallispan’s siege works to be destroyed, Cuneo reinforced and resupplied, and Gallispan’s LOC cut.  The Gallispan Army was forced to lift the siege and retire back across the Alps.

See the challenge for the gaming table?

Both armies need to be coerced (well, encouraged) into going onto the attack for very different reasons.  Conti needs to attack in order to destroy the Piedmontese relief force so that he can turn back to the task of reducing Cuneo.  Although outnumbered, King Emmanuele needs to attack in order to allow time to accomplish his strategic aims.  Without, of course, seeing his army destroyed. 

What did I come up with for victory conditions?

Currently, the criteria for victory are set as,

Victory Conditions:
Sudden Death:

Army Breakpoint Reached.

OR

At end of any turn,

• Franco-Spanish Army: Hold Madonna dell’Olmo, Cascina Pasquale or Tetto San Giacoma, Valentino, and have at least four units east of the road on the Piedmontese start line.
• Austro-Piedmontese Army: Hold Madonna dell’Olmo, Cascina Pasquale or Tetto San Giacoma, Valentino, and have at least four units west of the road on the Franco-Spanish start line.

Minor Victory:
Hold Madonna dell’Olmo at end of game and have fewer broken brigades than opponent.

Will these conditions effectively drive the narrative and direction of the tabletop battle to reflect the historical battle?  Time will tell.

Of course, having given some thought to the situation after reading this brief overview, how would you modify victory conditions to better reflect the situation and stated goals?

Thoughts on Lake Trasimene and D3 OHW

photo courtesy Gridbased wargaming

As reported in the battle account on Peter's blog (see Battle of Lake Trasimene), last week, Peter hosted a remote game to refight the Battle of Lake Trasimene.  If you have not already read Peter's account, I recommend doing so especially since scenario and background details are contained therein.  No need to retell the battle either.  Hannibal's Carthaginians drove many of the Romans into the lake and Flaminius' army perished on the banks of Trasimene.

Instead, today's post examines modelling of this battle on the wargames table with a closer look at Peter's variant of Neil Thomas' One-Hour Wargames (OHW) rules.  For simplicity, I refer to Peter's work as D3 OHW.  These rules can be found on his blog. 

First, how does one model the debacle that was the ambush at Lake Trasimene?  Having fought Trasimene several times using Commands & Colors Ancients (CCA), I have seen victory go to both Hannibal and Flaminius.  While the Roman Army is initially hamstrung by only having one command card to play, the outcome is not necessarily a foregone conclusion.  With careful play (and the right card), the Romans can hold on long enough to see the situation stabilize and fight back.  There are hazards to seeing the Romans triumph at Trasimene, however.  In one game, the Romans roared back to defeat Hannibal in spectacle fashion.  The ersatz Hannibal threw up his arms exclaiming that "this is not Lake Trasimene!"  Unfortunately, he never played CCA again...but I digress. 

CCA battlefield deployment.

How does CCA handle Trasimene?  With no facing, units cannot be struck in the flank.  Yes, a retreat will push Romans back into the lake but being supported and with Flaminius nearby, up to two RETREAT results may be ignored.  CCA game results show that Carthage wins about two-thirds of the contests.  In repeated playings and given a one out of three chance to overcome Hannibal, does this scenario model the battle satisfactorily?

What about Thomas' OHW?  Could this model Trasimene with more historicity?  While units in OHW have facings and flanks, and flank attacks are possible, a unit can turn to face after the first round of combat.  Being susceptible to a flanking attack improves the chance of launching a crippling ambush.  With no retreats, though, every clash is a fight to the death.  Having an advantage in heavy infantry, the Romans can prevail the longer each engagement lasts.

Peter's initial deployments
photo courtesy Gridbased wargaming

Now let's examine Peter's amendments to OHW.

Since a D3 is used for combat resolution rather than a D6 in the original, these rules are denoted as D3 OHW.  Unit elimination drops from 15 to 9 hits.

What are the other changes introduced?

• Morale Checks.  A unit suffering hit(s) must now take a morale check.  Pass, and the unit remains in place.  Fail, and the unit retreats.
• Retreats.  A unit failing a morale check moves to the rear six inches.  Friendly units in the retreat path are pushed back.  Encountering impassable terrain or enemy units forces unit elimination.
• Veteran Heavy Infantry.  Immune from taking morale checks.
• Army Resolve.  Each army has an Army Resolve computed before the beginning of battle.  This Resolve is decreased for each friendly unit destroyed and for each failed morale check. 

Do these changes to the base rules alter the nature of play and the Battle of Lake Trasimene specifically?

To recap the game, as the Carthaginians rush down toward the Romans marching along the banks of Lake Trasimene, Flaminius has great difficulty deploying his army.  With restricted maneuver space, only about one in three units turn to face the enemy.  At the tail end of the Roman march column, matters are even worse.  Carthaginian cavalry hit the enemy before there is time to deploy.  

Carthaginians charge down from the heights...

while the defile is blocked.

Romans struggle to deploy to face the enemy.

Hannibal's horsemen catch the enemy in flank!

Having been struck in column, the back end of the Roman column panics.  Two failed morale checks see two retreats.  Those retreating units crash into their supports.  Both supporting units are driven into the lake to perish.  Still reeling from the retreat, the wavering Roman is hit again and destroyed outright.  Carthaginian cavalry turn in to roll up the enemy flank.  In the Roman center, a third unit is compelled to retreat.  This retreat takes it to the banks of the lake.  With Roman infantry packed together near the defile, Carthaginian light infantry hit the enemy in flank.  Casualties are high until support comes up to drive off the enemy light infantry.

Romans are driven into the lake.
photo courtesy Gridbased wargaming

Two more Roman units bite the dust.
photo courtesy Gridbased wargaming

The battle is over.
photo courtesy Gridbased wargaming

But it is all too late.  Carthaginian cavalry break one more Roman infantry and all is lost.  Flaminius loses his army.

Did Peter's amendments allow the nature of the battle to be replicated on the table?  Yes, they did.  I thought tension from the Roman desperation was present on the gaming table throughout.  Flaminius struggled to deploy his army from march column into battle while being pressed by the enemy.  With little space to deploy, only a portion of the Roman Army turned before the enemy struck.  Overwhelmed, some Romans broke and fled as they were attacked in flank.  Their panic spread as supporting units were pushed back into the lake.  In minutes, it was all over.  Could the battle have played out differently?  Certainly.  That is why we play the game. 

Good fun especially as commander of the Carthaginian Army!  If you play and enjoy OHW but are searching for more depth and "realism" while maintaining the base game engine, I recommend giving Peter's D3 OHW rules a look. 

Thanks to Peter for hosting such an entertaining game.