Combat Overcrowding: Numerical Diminishing Returns

In vanilla, outnumbering your opponent is all you need to do to win. Doing something as minimal as bringing a single extra regiment to a fight can tip an even battle into a cascading slaughter. This mod ends that. Similar to how EU4’s flanking range meant only so many regiments could effectively engage at once. This mod brings that concept into EU5’s frontage system by modifying damage instead of disallowing regiments from fighting.

During battles, if one side outnumbers the other in non-reserved frontage(regiments engaged, or trying to engage), the larger side receives combat power penalties. The wider your formation stretches beyond the enemy’s, the less of your army is actually in the fight.

All modifiers scale with relative frontage, these are their maximum. As of 1.2.0 Light units have received bonuses/less maluses to improve their usability in difficult terrain.

• Heavy Infantry: up to -80% combat power.
• Light Infantry: up to -65% combat power.
• Heavy Cavalry: up to -65% combat power.
• Light Cavalry: up to -50% combat power.
• Artillery: up to -25% combat power. Fires from behind the line regardless of crowding.
• Auxiliary: up to -80% combat power.

Modifiers begin to apply once one side outnumbers the other by 25% frontage. This amount grows by 5% per age. In later ages, improved organization and technology allow armies to coordinate larger formations. Better drill, command structures, and battlefield communication mean more of your force can actually contribute. An Age of Revolutions army handles the same numbers that would have been chaos in the Age of Traditions.

• Only the larger side is penalized. The smaller force fights at full effectiveness.
• Equal battles start with no penalty. As regiments rout the gap widens gradually instead of cascading into total slaughter.
• More actively engaged troops always help, but each additional regiment contributes less than the last.
• Smaller, well-led armies punch above their weight.
• Quality investments like discipline, morale, and combat ability matter more relative to raw numbers.

Overcrowding = 1 – (smaller frontage × age multiplier / larger frontage)

Each unit type’s combat power is then reduced by its base rate × overcrowding:

• Infantry power: -80% × overcrowding
• Cavalry power: -65% × overcrowding
• Artillery power: -25% × overcrowding
• Auxiliary power: -80% × overcrowding

If the result is zero or negative, no penalty is applied.

Age multipliers:

• Age of Traditions: 1.25x
• Age of Renaissance: 1.30x
• Age of Discovery: 1.35x
• Age of Reformation: 1.40x
• Age of Absolutism: 1.45x
• Age of Revolutions: 1.50x

Example: 10 frontage vs 5 frontage in Age of Traditions
Penalty = 1 – (5 × 1.25 / 10) = 1 – 0.625 = 0.375
The larger side loses 37.5% of the base modifier per unit type: -30% infantry power, -24.4% cavalry power, -9.4% artillery power.

Again, no penalty applies until the larger side exceeds the smaller by more than the age multiplier. In Age of Traditions that means 25% more frontage. In Age of Revolutions, 50%.

This mod pairs well with the following for a more comprehensive military change, but all are standalone:

• Total Levy Combat Overhaul
• War Momentum