Over the years I've come across a number of simple but very effective game mechanisms, two of which I consider to be ground-breaking. These are EDNA and SCRUD.
EDNA (Ever Decreasing Number Allocation) was devised by Graham Hockley, and demonstrated at COW1990. Essentially, EDNA is a numerical value which represents an individual or unit's current willingness to move forward under fire. In other words, it reflects the current morale or 'will to combat'. As combat takes place and an individual or unit needs to see if they will do as requested, an EDNA test takes place, and if the result is negative, the EDNA is decreased. Once the EDNA reaches zero, the individual or unit is rendered ineffective.
In Mark Hannan's FULL METAL EDNA (published in THE NUGGET N108 in March 1996), the starting EDNA for all units was 8. Each time a test was required, 2D6 were thrown. If the resulting total dice score was less that than a unit's current EDNA, everything was fine ... BUT if the total dice score was more than the unit's current EDNA, the difference between the dice score and the current EDNA was deducted from the EDNA. The EDNA was therefore reduced.
An example of EDNA in operation
SCRUD (Simple Combat Resolution Using Dice) was devised by Tim Price, and was first outlined in THE NUGGET N80 in 1991. Tim Price described SCRUD as follows:
Looking back at both these mechanisms, I am struck by the fact that they would be very easy to slot into almost any set of wargame rules ... including my own PORTABLE WARGAME rules!
EDNA (Ever Decreasing Number Allocation) was devised by Graham Hockley, and demonstrated at COW1990. Essentially, EDNA is a numerical value which represents an individual or unit's current willingness to move forward under fire. In other words, it reflects the current morale or 'will to combat'. As combat takes place and an individual or unit needs to see if they will do as requested, an EDNA test takes place, and if the result is negative, the EDNA is decreased. Once the EDNA reaches zero, the individual or unit is rendered ineffective.
In Mark Hannan's FULL METAL EDNA (published in THE NUGGET N108 in March 1996), the starting EDNA for all units was 8. Each time a test was required, 2D6 were thrown. If the resulting total dice score was less that than a unit's current EDNA, everything was fine ... BUT if the total dice score was more than the unit's current EDNA, the difference between the dice score and the current EDNA was deducted from the EDNA. The EDNA was therefore reduced.
An example of EDNA in operation
- A unit with a starting EDNA of 8 wishes to move forward. It throws 2D6 and scores 5. The total dice score is less than the current EDNA, so the unit does as requested.
- The unit wishes to move forward again. It throws 2D6 and scores 10. The total dice score is more than the current EDNA, so the unit's EDNA is reduced by the difference to 6. (10 - 8 = 2; 8 - 2 = 6)
- The unit wishes to move forward again. It throws 2D6 and scores 7. The total dice score is more than the current EDNA, so the unit's EDNA is reduced by the difference to 5. (7 - 6 = 1; 6 - 1 = 5)
SCRUD (Simple Combat Resolution Using Dice) was devised by Tim Price, and was first outlined in THE NUGGET N80 in 1991. Tim Price described SCRUD as follows:
These rules are intended to be used as a simple method of resolving the combats that take place within the larger framework of a game. They are meant for those battles that take place in the boarding actions of Naval Games, the Open Battles that are encountered when playing Matrix Games, and the confrontations that appear during back-to-back Map Games. In short, those small, but vital, elements that are part of the whole that makes up a wargame, that have to be resolved quickly or the Game itself grinds to a halt.The mechanism works as follows:
- Roll 1D6 for each unit (both friendly and enemy) taking part in the combat
- The resulting dice for each side are lined up opposite each other, highest first. (If one side has more dice than the other, any dice that are extra, and score less than the lowest dice of the side with the fewer dice, are ignored)
- Compare the paired off dice
- The higher dice beats the lower dice (Equal scores are ignored)
- Each dice defeated represents a push-back in large combats, or a death in smaller combats. Three such defeats eliminate one of the opponent's units
- Two opposing forces (Red with three units and Blue with five units) come into combat
- Red throws three D6s and scores 6, 5, 2
- Blue throws five D6s and scores 5, 4, 3, 2, 2
- The dice are lined up, highest first and paired off
- Red's 6 is paired up against Blue's 5; therefore, Red wins
- Red's 5 is paired up against Blue's 4; therefore, Red wins
- Red's 2 is paired up against Blue's 3; therefore, Blue wins
- Although Red is the weaker of the two opposing forces, it has inflicted twice as many casualties on Blue than Blue has inflicted on Red
Looking back at both these mechanisms, I am struck by the fact that they would be very easy to slot into almost any set of wargame rules ... including my own PORTABLE WARGAME rules!
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Some nice ideas there and I think the SCRUD system, or something similar, is used in the Sword & Spear rules.
ReplyDeleteSteve J.,
DeleteAlthough the two mechanisms have been around for quite some time (more than 25 years), they never seem to have been picked up and used in many sets of commercial rules.
All the best,
Bob
Those are both very interesting mechanisms Bob - thanks for sharing them. I can see them both being of use particularly in Campaigns.
ReplyDeleteMaudlin Jack Tar,
DeleteSCRUD has all sorts of uses, particularly for things like melees or small actions during a campaign that are not worth setting up a tabletop battle for (e.g. a fight between opposing outposts).
All the best,
Bob
EDNA and SCRUD are indeed two useful mechanisms. I've used SCRUD in my ACW house rules for over 10 years. SCRUD is of course a more elaborate variant of the basic combat system found in RISK. The nice thing about SCRUD is that modifiers - depending on tactical situations - can be defined as a + or - on the number of dice thrown instead of a modifier on the number rolled.
ReplyDeleteEDNA was presented in a magazine article (Wargames Illustrated 38, by Graham Hockley!) to run a game featuring a single volunteer who had to run towards the gate of an Afghan hillfort, place the dynamite, and blow up the gates. In my database of magazine articles (http://snv-ttm.blogspot.com/p/wargames-magazine-database.html), I find another article by Graham Hockley, Practical Wargamer Nov 1992, again about EDNA.
Phil Dutre,
DeleteIt’s years since I played RISK, but I seem to recollect that the combat mechanism is similar to SCRUD. I understand that the latest iteration of SCUD uses different coloured dice for different quality units.
Now that you mention it, I seem to remember Graham’s game being run ar a wargame show ... where it was very well received.
All the best,
Bob
This is what I was going to say, SCRUD seems an awful lot like combat in Risk! Nothing wrong with it, Risk keeps it as simple as possible (KISS SCRUD Risk! LOL). Its nice when playing simple games or with people new to wargaming.
DeleteI'm glad your first post of the year is about combat resolution systems! I found a new one in Tabletop Game 1975 rules,Rules for the Napoleonic period. They use a system of modifiers and a combat resolution calculator which is a sort of decoder ring that the player cuts out and assembles. Line up the modifiers with the number of troops and is gives you a number of casualties in that round of combat.
It's pretty detailed and I've been working on finding a way to use it in your PWg rules. I like how it reduces the random effect of dice and forces a player to use better tactics.
Does anyone reading this blog know of other rules that use a similar paper disc calculator? I'd like to see how other people have implemented it.
Thank you and Happy New Year.
Mr Pavone.,
DeleteI’ve seen the circular slide rule style of calculator in other circumstances (a calculator for nuclear fallout springs to mind ... which rather dates me) but never in a wargame context. I’d be interested to see how it would work.
May I also wish you a Happy New a year.
All the best,
Bob
Funny you should mention it, but I have that fallout calculator too. It's still buried in the back of that old US Army manual.
DeleteYou can find the rules on scribd.com, just search the title I gave.
It's definitely fun to play around with. It's easy to see how trading terrain advantages, initiative, careful planning etc for masses of troops works out. Hit them with a human tsunami or skillfully maneuver your skirmishers into position and you can turn the tide against a more powerful enemy.
I've seen quite a couple of these circular devices. I think Featherstone's book Advanced Wargaming has some of these, and I remember at least a Wild West gunfighter game. If you want I can scan them in. But anyway, these are usually used as a look-up tbale, not really a calculatar as such. Circular slide rules are a wholly different matter ... ;-)
DeleteMr. Pavone,
DeleteI think that the old fallout calculator was pretty well NATO standard issue, and I’m sure that there are loads of them still in circulation ... or hidden away in people’s lofts or basements.
I’ll look at the rules later this evening, as the idea sounds interesting ... although I’m not sure how it would work with my PW rules.
All the best,
Bob
Phil Dutre,
DeleteI think that the Wild West gunfighter rules were from the Table Top Games stable, as mentioned by Mr. Pavone. It seems as if it might have been a mechanism favoured by one of their designers.
All the best,
Bob
Mr. Dutré I'd love to see those calculators. If you could email them to me I'd appreciate it very much. You can find my contact info by clicking my name.
DeleteMr. Pavone,
DeleteI hope to include images of the calculators featured in ADVANCED WAR GAMES in a forthcoming blog entry.
All the best,
Bob
I have that circular calculator from the Tabletop Games Once upon a Time in the West rules somewhere. I'll dig it out and send over some pictures and explanation about it. The rules were by Ian Beck and John Spencer.
DeleteDave,
DeleteThat’s very useful information, and if you send me the images etc., I’ll include them in a blog entry.
All the best,
Bob
In the last sentence of the EDNA explanation, shouldn't it read = "BUT if the total dice score was MORE than" ?
ReplyDeleteNigel Drury,
DeleteYou are quite right, and I’ve since changed the wording.
All the best,
Bob
I have a question about the SCRUD example. In the example, Blue rolls 2 more dice than Red. Why are those two dice not counted as automatic successes as the numbers they roll are obviously greater than Red's zeros?
ReplyDeletePatrickW,
DeleteThe extra dice are ignored because the side throwing more dice should - in theory - stand a greater chance of throwing higher dice scores.
In the example, Blue has thrown five dice, which gives them a greater chance of scoring higher dice scores than Red has. To give Blue two automatic ‘hits’ because it has thrown two more dice than Red would seem to be giving a Blue an even greater advantage than would seem fair.
All the best,
Bob
I've seen many different variants on SCRUD - it is rather easy to playa round with number of dice, types of dice etc. As for unpaired dice, I often use the rule that any unpaired dice also count towards whatever you what you count if they score over half of the die type. E.g. an unpaired D6 needs a 4, an unpaired D10 needs a 6 etc. But it's as Bob says, having more dice already gives you a strong advantage.
DeletePhil Dutre,
DeleteOne of the advantages of SCRUD is its inherent ability to be modified - often quite drastically - without getting broken. For example, I’ve tried D10s vs. D8s vs. D6s for elite vs. average vs. militia combats.
All the best,
Bob
I have heard of both EDNA and SCRUD (and recall reading the WI38 Graham Hockley article) but have never really done anything with either. Actually, I'm not sure I ever knew how SCRUD worked! Seems to me that both would have a fine solo play application.
ReplyDeleteI've just tried a Green (5 units) vs Orange (3 units). First battle - you won't believe this: Green: 6,6,6,6,3 vs Orange 6,6,6. I presume this one would be inconclusive, with trivial (no) loss to both sides.
Second pass: Green: 6,5,4,4,3 vs Orange 6,4,2
Pairing: 6-6, 5-4, 4-2 Orange lose 1 SP from 2 defeated units, which are forced back...
I'll have to try this in a game. Maybe some further event in the Lyndhurst Chronicles as the Duke of Kent decides on a punitive expedition into Lyndhurst...
Cheers,
Ion
Archduke Piccolo (Ion),
DeleteSCRUD is a very useful game mechanism, and I’m thinking about incorporating it into a set of rules as a means to resolve close combat.
In your second pass, just imagine what would have happened if Orange had been elite (and thus added 1 to all their D6 scores) and Green had been militia (and thus reduced all their D6 scores by 1). The results would have been:
Green: 5, 4, 3, 3, 2 vs. Orange: 7, 5, 3 ... with Green losing 1 SP from two units.
I have a feeling that you’re going to find all sorts of uses for SCRUD.
All the best,
Bob
Bob,
DeleteI think modifying the results of the dice is a bad way of introducing modifiers in SCRUD. The 'natural' way to add modifiers to SCRUD is to increase/decrease the number of dice, or alter die types.
The reason is that once you have thrown the dice, you want to pick them up, sort them in order, etc. If then you also have to do some mental calculations about what numbers need to be modified, it becomes a bit unwieldy.
At least, that's my experience after many years of using SCRUD in my ACW house rules for resolving close combat between units, and SCRUD is used to determine the number of men lost on both sides.
Phil Dutre,
DeleteYou make an excellent point. As I tend to fight my wargames solo, I had not thought about how adding bonuses or subtracting penalties to D6 dice would work with an opponent in a face-to-face wargame.
Perhaps the way forward is to use specially modified dice (as Tim Price has in one of his recent games). He made his special D6 dice using blank dice and stickers.
All the best,
Bob
Bob
ReplyDeleteI've used an EDNA mechanism in my own Napoleonic rules of the last twenty years. It determines the success of any manoeuvre beyond simply straight forward and contributes about fifty per cent to the unit's firepower calculation. It also is the base number for melee. Very handy simple representation of a lot of 'stuff' bundled into one measure. The rules were published in MWwBG a few years back.
Cheers
Andrew
Rumblestrip (Andrew),
DeleteIt sounds as if you have more practical knowledge of EDNA's use than I have ... and in ways that I have only just begun to consider.
Do you know if the rules are available anywhere online?
All the best,
Bob
Are these the "What, No Wellington?" rules in MWwBG 388?
DeletePhil/Bob
DeleteThey are indeed. Since tweaked slightly further to change the probability curves a little.
Cheers
Andrew
I always thought that EDNA was clever, but could never see a practical application for it. All of the games in magazines simply used the basic mechanism, so whilst you were creating a narrative of sorts, the game played itself with no actual input in terms of decisions by the player.
ReplyDeleteAre there some examples of it as a mechanism in a wider game?
Kaptain Kobold,
DeleteFrom Rumblestrip's comment (see above), it would appear that he has used the EDNA mechanism in a set of rules that would illustrate its wider use in a wargame.
All the best,
Bob
Bob/KK
DeleteYes the idea was to have the EDNA be the key stat for most of the game and have it affected by excessive manoeuvre and fire. Longer range sniping might remove no figures from a unit, but could gradually render it ineffective (over a long time) by reducing its EDNA (perhaps all its officers and NCOs were casualties?). A unit might wear itself out marching and countermarching if its initial placement proved to be unhelpful. A unit's general wellbeing/self-perception seemed a reasonable basis for determining its base value in melee. The rules as written lack a C&C system but one of any number is straightforwardly bolted on. Also I think I failed to explain the excess ranges for musketry in the article as representing otherwise invisible skirmishers.
I don't believe the article is available online anywhere but I can easily email you a copy of the rules.
Cheers
Andrew
Rumblestrip (Andrew),
DeleteIt sounds as if you have made extensive use of EDNA in your rules, and I'm sure that Kaptain Kobold and I would like to have sight of the article if you could email it to us.
All the best,
Bob
Bob
DeletePM'd you
cheers
Andrew
Rumblestrip (Andrew),
DeleteMany thanks for sending me a copy of the article. I’ll pass it on to Kaptain Kobold as soon as I can.
All the best,
Bob
Stu Rat,
ReplyDeleteThe explanation is taken from the article written by EDNA’s designer, and I think that he wanted the excess dice scores ignored. That said, your interpretation makes sense.
All the best,
Bob
I've recently been revisiting both these mechanics as I have been working on a a vietnam war based command post type game utilising WhatsApp and walkie talkie apps on phones.
ReplyDeleteI've been playing around with doing rerolls instead of modifiers, as it seems to me an easier mothod for my head.
In curtain situations, certain gave numbers can be rerolled.
I'm still trying things out regard to number fo possie rerolls, face numbers that can be re riled.
I'm also playing a round with just allowing re rolls as this may create a choice.
Example I have rolled several 3s being beaten by 4s.as an loss by 1 it would be a recoil. If I gamble and roll again I could improve my situation or worsen it. Which seems to me to create more uncertainty or variation of results and to add a decision lacking from just a simpler +/-.
Also been thinking in using different sized dice.
With enda been experimenting with different starting values, a starting baile of 10 and roll 2 d8... Though I'm not yet clear on how that will affect probabilities and rangw of results.
Obviously the elegance of the base mechanics is their adaptability.
Now just needing to make sure elegance is not lost.
The European Historical Combat Guild,
DeleteIt sounds as if your experiments with the SCRUD and EDNA mechanisms are yielding interesting results, and I can understand why you have opted to try revolting dice rather than adjusting the scores with modifiers.
Good luck with your project.
All the best,
Bob
Just a typo, obviously, but shouldn't it be "Ever" instead of "Every"?
ReplyDeleteEmarsk,
DeleteYes, it should be … and the error will be corrected.
All the best,
Bob
Just discovered SCRUD in WI 064, and am planning to try it today for a "free kriegspiel" game I'm experimenting with on Discord. I will look for EDNA in WI 038 next.
ReplyDeleteJennifer,
DeleteSCRUD and EDNA are both very useful wargaming tools, and I am sure that you will find all sorts of wargaming applications.
All the best,
Bob