Wednesday, March 29, 2017

Chainmail Variant Rule - Post-Melee Results

Chainmail has many ways in which to recommend itself as a fast play set of big battle Medieval rules.  One of the more troubling areas, however, is in post-melee morale.

To a modern eye, this is a set of mathematical calculations that will slow down the flow of the game.  It is actually all just simple math (addition and multiplication, for the most part), but it does seem to be out of favor with modern war game design philosophy.

To that end, I offer the following system (but first, present the current system, for comparison).

The Post-Melee Morale system, as is
On page 15 of the rule book, there is a procedure for calculating Post-Melee Morale.  It involves three factors, added together:
  1. A factor for the side that took fewer casualties in the melee.  This is the difference between the two casualty counts, times a d6 roll.  Only the side that took fewer casualties gets this factor.
  2. A factor based on the current size of the unit, as number of total figures times their Morale Rating.  Both sides get this factor.
  3. A factor based on who has more figures surviving after the melee.  This difference between the two totals of surviving figures, and is multiplied by a d6 roll.  Only the side with more figures gets this factor.
Add up the factors.  Each side will have at least one of these (number 2), but only one side or the other will benefit from the others (numbers 1 and 3).

Compare the two totals, and then consult the difference on this table:

0-19 differencemelee continues
20-39 differencelower total side moves back 1/2 move, but in good order
40-59 differencelower total side moves back 1 move, but in good order
60-79 differencelower side retreats 1 move
80-99 differencelower side routs 1 1/2 move
100+ differencelower side surrenders, and victorious side may continue a charge if possible, leaving behind 1 guard per 5 prisoners

Factor number 2 above, is the current total value of each unit - meaning the total number of remaining figures, multiplied by the Morale Rating of the figures.  In a mixed unit, each figure is multiplied by it's own Morale Rating, and then the subunits are added together.  Here are the Morale Ratings:

Light Foot and Levies4
Heavy Foot5
Elite Heavy Foot6
Light Horse6
Armored Foot, Janissary7
Medium Horse, Landsknechte8
Heavy Horse, Swiss Pikemen9

The New Post-Melee Morale System, Proposed
First, the concept - This method involves taking a morale test.  Both sides calculate what their target number would be, and the lower total tests first (2d6, trying to roll the target number or less).  If the first test fails, then depending on the nature of the fail, it will consult the Post-Melee Morale Test Results table below.  If the first test passes, then the second unit will make a test against it's target number.  If the second unit fails, then it will also suffer the results from the table below.  If it passes, then both units are still engaged in combat, and the melee continues next turn.

Method -
Each side determines their target number.  This is based on the Morale Rating from the above table.  To that number, add/subtract the following:
+1, if larger than the enemy
+1, if took fewer casualties than the enemy
-2, if 1/4 of the original unit is dead
-4, if 1/3 of the original unit is dead
-6, if 1/2 of the original unit is dead, or more

Each side will calculate this target number.
The side with the lower target number tests first.
If the first testing unit fails, then it consults the results table below.
If the first testing unit passes, then the other side will test.
If the second unit has to test, and it fails, consult the results table below.
If the second unit has to test, and it passes, then that means both sides have passed, and the melee continues.

In practice, this amounts to a quick comparison of target numbers, and the lower number tests.  If it fails, that is the end.  If it passes, then the other side tests.  That's all.

If the two target numbers are tied - both sides roll.  Either side that fails will suffers the results.  If (extremely rarely) both sides try to surrender, then both sides rout instead.

Post-Melee Morale Test Results
Miss -1back 1/2 move, good order
Miss -2back 1 move, good order
Miss -3retreat 1 move
Miss -4rout 1 1/2 move
Miss -5 or moresurrender

Miss -1, etc, means the 2d6 dice roll missed the target number by 1 (i.e. target=7, and 8 is rolled on the dice).

Here is the whole process reduced to a flow chart, and with the Morale Rating, and Test Results charts included (click to make bigger/more readable).

Multiple Units
In order to apply this method to multiple units, calculate the Target Number for all units involved on all sides.
  1. Starting with the lowest value unit, begin testing.  Apply results to each unit, as it tests.
  2. If any units have the same Target Number, always test them simultaneously.  
  3. Apply the "Took Less Casualties" modifier to each unit on the side that took fewer overall.  
  4. Apply the "Larger than the Enemy" modifier to the side that has more total figures (counting all units involved), to each unit on that side.  
  5. Apply the modifiers for unit loss to each unit individually.
  6. Stop testing when only units from one side or the other remain in contact.
  7. If a unit is to Surrender, but the final results have a friendly unit still in contact, then that unit Routs instead.
Example - A heavy foot unit (12 figures), and a medium horse unit (9 figures) hit a large armored foot unit (24 figures).  In the melee, the heavy foot unit loses 4 figures.  The medium horse unit loses 2 figures.  The armored foot unit loses 5 figures.  Start by calculating Target Numbers:
  • Heavy Foot - base value of 5
  • Medium Horse - base value of 8
  • Armored Foot - base value of 7
After the Melee, the Armored Foot unit is larger (19 remaining, vs a total of 15 remaining on the other side).  The Armored Foot also took fewer casualties than the other side (5 figures killed, vs 6 figures killed).  So the Armored Foot unit gains a +1 for Fewer Casualties, and a +1 for larger than the enemy.  The Heavy Foot have lost 1/3 of their figures, so take a -4.  That makes the Heavy Foot unit have a target of 1, the Medium Horse unit still has a target of 8, and the Armored Foot unit has a target of 9.  
Rolling, in order, for the Heavy Foot (roll of a 6, which means that they will surrender to the Armored Foot).  The Medium Horse is next, and must test (even though the Heavy Foot failed) because there are still units in contact from both sides.  The Medium Horse rolls a 7, and remains in contact.  The Armored Foot rolls a 6, and also remains in contact.  The melee will continue next turn between the Medium Horse (with 7 figures remaining) and the Armored Foot (with 19 figures remaining).
Because the Heavy Foot still had a friendly unit in contact after all tests, rather than surrender, they rout instead.

In practice, trying this out with just nominal units fighting it out using pencil and paper, this works fine.  It rewards the better quality unit (very medieval), but also modifies that by the realities of the melee.

This method seems to work, it only has to be put into practice in a few solo games.  If anyone reading this tries it out, please let me know your results.


Ed M said...

Certainly brings up memories of the days when most rules involved such numerology of one kind or another. I'm going to have to break out my copy of "Chainmail" and review the system to wrap my head around it, and your alternative. Thanks for working this out.

Charles Turnitsa said...

Thanks Ed - by the way, I just tweaked it, and added the flow chart (which is printable) and the "Multi-Unit" example.

Jonathan Freitag said...

The original melee process, as presented, seems confusing, math intensive, and perhaps even quasi-double counting. Your refinements with flowchart provide a much more streamlined approach. My question: Do the probabilities of success work out about the same under both systems?

Charles Turnitsa said...

Jonathan, that is a good question. If we assume that the original method is the "true" model (at least according to the original rules writers), then I would have to validate my model against theirs. I think that I will try that in one more article on this subject (set up a few example situations, unit against unit, and assuming average dice rolls for casualty generation, then work out the post-melee results both ways, to see what the odds are like).

I know that I tried to make sure my model rewards the same things as the original model (difference in troop quality, as seen by the morale rating; difference in unit size; and difference in casualty generation). The only thing I introduced was the modifier for how many figures have perished so far in combat, and that is a big modifier (-2, -4 or -6 depending on accumulated casualties suffered so far). Maybe I should try it with and without that modifier.