Ardennes ’44 2nd edition from GMT, by Mark Simonitch is a tightly designed game that needs very few changes to be realistic and challenging for both sides. After numerous plays, these are the balance conditions I recommend.
Factor limits – the original had a 15 combat factor limit in each combat, which strongly favored the US because it made high odds attacks virtually impossible against reasonably strong positions (more than a single battalion, pretty much). This was later made and optional rule and most now play without it, which tends to favor the Germans in comparison.
I prefer to use an 18 factor limit (the same used in Normandy ’44 incidentally), with one additional rule. The factor limit is raised to 24 factors if and only if the defending hex is ZOC bonded by the attackers, such that it will have to conduct a desperation defense on any retreat result. This higher limit reflects the ability to bring more total force to bear if the defenders are surrounded and can be approached from more directions at once.
These 18 and 24 factor limits are always counted *after* any halving due to terrain, supply, or combat coordination effects.
Jabos table defense – After the weather improves the US gets Jabo table random defensively shifts against all German combats, in addition to 3 offensive air power shifts each turn. These are too powerful and end the period of possible German attacks too soon. The revision is to use a Jabo table that is 1 shift for a roll of 1-3 and 0 shifts on a roll of 4-6. This is still an occasionally important defensive benefit but not as brutal as the original.
Desperation Defense EX results – The original specifies that the attacker must lose an armor step in any combat in which they received an armor shift and suffer an EX result. The DD table includes EX as the way it specifies 1/1 mutual losses, and this together implies that defenders who get those EX results will “eat” attacking armor. US airborne units in particular routinely DD with elite unit quality shifts and can thereby “devour” German armor, when historically they were very light on AT weaponry. So the change is just that the EX required armor loss rule applies *only* to EX results obtained on the *original* CRT. Treat DD table EX results as 1/1 step loss with the defending lead unit required to take its step loss while the attacker picks any step to fulfill their loss result.
Fuel table rolls – in the original once the fuel table comes into effect the Germans always roll once on each of the north and south tables. Instead roll first with 1-2 meaning only the north checks, 3-4 only the south checks, and 5-6 both check (as in the original). This will reduce the number of German formations out of supply for fuel reasons and allow the fight to be played out between the armies instead of deciding it with random stalls.
Formation coordination limits – in the original either side is allowed to designate a lead formation for any attack, cross attach one unit from another formation, and also use one army level or unattached unit at full strength. Units beyond these categories could be included at 1/2 their rated combat factors. In practice these limits are not tight enough to prevent players from completely scrambling their formations, since changing cross attachments and lead formation designations allows virtually all units to fight at full strength in all combats.
The solution is to allow all units from the lead formation and *either* all army level or unattached formations to join them at full strength*or* just one unit from another actual formation to attack at full strength in one combat. But not both. Any units beyond these limits can participate but do so at 1/2 strength. Defenders always participate at full strength (as in the original). Note that the rule allowing multiple army level units to fight together also encourages building mini formations out of these or around e.g. the 150 Panzer Brigade.
Optional bloodier CRT
Some find the combat system in Ardennes ’44 too forgiving to defenders and too “bloodless”, in the sense that attacker odds between 1-1 and 4-1 mostly just reduce attacker losses and increase the chances the defenders will be forced to retreat (and unable to DD), while not directly increasing the defender’s expected losses. For those interested in trying more decisive combat, I suggest the following optional change to that CRT.
Roll a second colored die with the normal combat roll. If the result is DR3 or DR4 and the colored die is 1-3, the defender suffers a step loss in addition to the retreat result. Otherwise the colored die is ignored.
Note this will increase expected defender step losses by 1/12 step on 3-1 combats and by 1/6 step on all combats at 4-1 odds and above. It favors the Germans, but not unduly so. If using this option, be sure to include some form of the attacking factor limit (like the 18 factor rule above with 24 factors only allowed vs ZOC bonded defenders), otherwise the task becomes too easy for tactical attackers.