War Machine, revised: Mass Combat for 4e

Following on from my look at Strongholds and Henchmen for 4e, here’s how to use Classic D&D’s War Machine rules in Fourth Edition D&D. These provide a terrific way to simulate the clash of steel between hundreds, thousands or even tens of thousands of troops on the field of battle. You will need the D&D Rules Cyclopedia to use these in full, but even if you lack that worthy tome I hope you find this of use. Read on!

The War Machine mechanic itself is simple, yet at the same time surprisingly crunchy and detailed for a Classic D&D subsystem. Each body of troops has a Battle Rating calculated from the quality of leadership, training, equipment, experience and special abilities. This is modified on the field of battle to take into account differences in between opposing force sizes, morale, terrain, immunities and troop fatigue. Each side rolls d100 and adds the Battle Rating simulataneously. Compare the difference between the two on a Combat Results Table. This tells you how many losses to deduct from each side, apply fatigue and adjust troop locations as required.

That’s one battle. String ’em together and you’ve got a war!

As with many things in Classic D&D it’s one of those things that’s far easier to play than it is to explain with only the initial Battle Rating taking any time to calculate. Entire battles between many thousands of troops can be played through in less time than it takes to run a couple of encounters. Seriously.


Battle Rating
To work out the Battle Rating of the troops, we need to add together five numbers – Leadership, Experience, Training, Equipment and Special. These calculations are the main part of War Machine which needs to change to take into account Fourth Edition terms. This is then modified according to whether a sizeable portion of the troops has missiles, mounts, magic or can fly.

Leader’s level + total of Leader’s Intelligence, Wisdom and Charisma ability bonuses + 2 per 1% of troops that is Paragon Tier or above

Any war can be won or lost based on the strength of it’s leadership. Add the Leader’s level to his Int, Wis and Cha attribute bonus then add +2 for each 1% of the troops that is 11th level or above.

Example: Sir Garaunt of Fellwyr is the noble Paladin leader of 30,000 worthy troops and attendants. He is 14th level and the total of his INT+WIS+CHA attribute bonuses is +9. His force includes a 600-strong Honour Guard of 11th level Tiefling Swordmages which nets a further +4. His total Leadership is 27.

Example: Bugrun the Gnoll Ranger leads a small force of 135 outlaws. He is 6th level with attribue bonuses totalling +4. There are no Paragon Tier troops. His total Leadership is 10.

[Average Warlord level x 3] + [Average Troop level x 2] + 1 per Victory -1 per Rout

Any army needs officers and captains who are able to lead the troops and make on the spot tactical decisions. This is where the 4e Warlord class really comes into it’s own and show their worth on the field of battle. Take the average level of all the Warlords in your army, and triple it. Next, take the average level of the rest of the troops and double it. Add the two numbers together and modify by +1 for each victory in the last 10 years, and -1 for each rout.

Example: Sir Garaunt’s chain of command includes 800 Warlords with an average level of 6th. His average overall troop level is 5th and they can boast of 6 victories and no routs to their name. Their Experience total is (6×3 + 5×2 + 6) = 34.

Example: Bugrun’s sole Warlord is his lieutenant, a 3rd level Night Goblin. His average troop level is 2nd and he has 3 victories but one recent rout to his name. The outlaw band’s Experience total is (3×3 + 2×2 +3 -1) = 15.

[1/week training] + [1/week training with Leader] + [1/month on duty]

Experience counts for little if the troops don’t know how well to fight effectively as solid units. Add one for each week that the army has trained together (to a maximum of 20) plus a further one for each of those weeks where the Leader was also present during the Training week. Gain a further +1 for each month that the units have been on active duty.

Example: Sir Garaunt’s troops are nothing if not well-trained with a full 20 weeks’ barrack training under the belt of every soldier. Unfortunately, Sir Garaunt himself was only present for the first and last week – he is a busy man, after all. They have been on active duty for 4 months for a total Training value of (20 + 2 + 4) = 26.

Example: Burgun has been keeping his ragtag band of outlaws busy; they have spent 10 weeks learning how to effectively defend their forest home, and all of that time has been spent under his watchful eye. They have been together for eight difficult months so have a Training value of (10 + 10 + 8 ) = 28.

0 if poor, 5 if average, 10 if good, 15 if excellent
+5 is armed with a second weapon of same quality
+5 if average AC is 18 or greater

Sometimes the only difference between evenly matched foes is the quality of their weaponry. Just ask an English Longbowman. Similarly, even a peasant rabble can become a force to be reckoned with when they’re equipped with chanmail and good halberds.

Award 5 points if the equipment is average (ie, list cost), 10 if good and 15 if excellent. Poor quality equipment nets 0 points. Add a further 5 points if the troops have a second weapon of at least the same quality, and +5 if their average Armour Class is 15 or higher.

Example: Sir Garaunt prides himself that his army is well equipped with Good quality blades and/or bows. They are all at least AC 18 – usually a combination of Chain and Shield, though some cavalry troops wear Full Plate. The Equipment total is (10 + 5) = 15.

Example: On the other hand, Burgun’s outlaws take what they can get. Thanks to the covert assistance of a local blacksmith at least it’s well maintained, if only Average quality. All troops carry a second weapon – usually a combination of longsword and shortbow, or handaxe and sling. Most are lightly armoured in Leather so their total Equipment bonus is (5 +5) = 10.

2/per 1% of force that is Elite

Finally, give 2 points for every one percent of the force with the Elite keyword. While the vast majority of troops in any force should be made up of regulars – Minions and standard races and monsters – these are the Special Units; the ones with remarkable abilities and staying power to make a difference in the war. This includes all Monsters and NPCs with templates and/or class levels, as well as any monster classified as Elite on the Monster Manual.

Along with his 600 Tiefling Warlords and 800 Warlords Sir Garaunt’s forces also include a contingent of 250 Eladrin Cavalry and 450 Eladrin Fighters. There is also a small (undisclosed) special operations unit of 75 Halfling Rogues. These make up a total of 2,175 troops – 7.25% of his total complement for 14 Special points.

Example: Bugrun’s meagre force of 135 is primarily made up of Human Bandits, though there’s a sizeable number of Rogues, Fighters and Rangers. He can also call on the support of three Elven Druids should the need arise. In total there at 18 Elite troops out of 135 for 26 Special points.

Add those together to get the Basic Force Rating and overall Troop Class. This is a purely subjective assessment of the troops’ overall ability and is designed to help quickly gauge the relative differences between two armies.

Basic Force Rating Troop Class
10-20 Untrained
21-35 Poor
36-55 Below Average
56-70 Fair
71-80 Average
81-100 Good
101-125 Excellent
126+ Elite

Example: Sir Garaunt’s Basic Force Rating is 116 – their Troop Class is (unsurprisingly) Excellent.

Example: Bugrun’s Basic Force Rating is 89 – their Troop Class is a plucky Good.

That’s the hard part done with. See? Wasn’t too difficult. Next time we’ll put the armies to the field and show how the terrain, ratio and tactical modifiers can help turn the odds of war. Till then!

5 Comments on “War Machine, revised: Mass Combat for 4e”

  1. @Skeolan As a fellow pencil-necked math geek, I thought about that as well. But then I left it as it is for two reasons:

    1) Simplicity
    2) I quite like the idea that this reflects inexperienced officers who tactically end up doing more harm than good :)

    That’s the price you pay for having poor command structure, I guess.

    @Elton Oh I dunno. I’ve used the War Machine rules from the D&D Rules Cyclopedia from everything from Third Edition D&D to Traveller and Mutants & Masterminds with little difficulty. All I’ve done here is added a few 4e specific terms into the mix. I’m sure they’re usable for any system or edition.

  2. Mr. Wulf,

    Thanks for another excellent post.

    From a purely pencil-necked math-geek position:

    “Experience =
    [Average Warlord level x 3] +
    [Average Troop level x 2]
    + 1 per Victory
    -1 per Rout”

    Shouldn’t there be some factor for the proportion of Warlords to other classes? It seems like your intent is to suggest that Warlords within an army count 1.5x as much as regulars for determining the overall experience of the unit.

    But according to the formula as given, in your Bugrun example, if the army were to add ten level-1 Warlords to its ranks – its Experience rating would go DOWN to 9.5.

    I imagine it ought to be more like

    [Average Warlord level x 3]*[No. of Warlords / Army size]
    + [Average Troop level x 2] * [No. of non-Warlords / Army Size]
    + 1 per Victory
    -1 per Rout

  3. Very cool – looking forward to part 2.

    My 4E group is just starting Trollhaunt Warrens and I see a great opportunity to do part of Skalmad’s attack on Moonstair via the War Machine.

  4. Excellent post my man! I’ve been waiting for someone to do just this very thing. At first I thought about how I could use this for my low-level group, but now after re-reading your post, I’m envisioning wonderful applications for my epic level campaign as well. Again, thanks and obviously, can’t wait for part two.

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