Imperator - Development Diary #21 - 22nd of October 2018

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Studio Manager Paradox Tinto
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Hello and welcome to the 21st development diary for Imperator. This time we’ll go into how land-combat works in the game, and talk about Combat Tactics.


Combat in Imperator occurs when two armies is in the same city. The army first in the city is considered the defender, unless the other side has control over fortifications in the province.

The battlefield have 60 different positions for each side, as well as a reserve where cohorts currently not fighting will be. Armies will be organised with infantry in the middle, cavalry on the flanks and ranged support in the backline when possible.

Each day, each unit will fire on one target in front of them, or towards the side, if they have a high enough flanking ability.

Damage is determined by adding up the dice with the combat modifiers from terrain and leaders, where a total of 0 or below gives 2% damage, and the maximum of 15 from terrain and dice gives 30% of damage.

The impact of diceroll on a battle is far less in Imperator than games like V2, EU4 and CK2, as the range of dice is smaller with just a 1d6 being rolled, rather than the usual 1d10.

Crossing a river, or doing a naval landing, gives -1 to the attacker.

Mountains gives +2 to the defender, while Hills, March and Forests gives +1 to the defender.

Leaders impact combat as well, with the difference in martial giving a bonus to the one with the highest martial.

Then the damage value is modified by the following before being applied to the target. (Please note that all damage is done after the round of combat is calculated, so it’s not beneficial to fire first.)

If you are firing from the back line, you are basically at 50% efficiency.

The attacking units discipline is a positive modifier for damage, and this discipline can be either the country, or individual modifiers of discipline down to cohort., and loyal regiments will do slightly more damage.

Each type of unit can also have bonuses for fighting better or worse when doing damage or receiving damage, and also for fighting in certain terrains. Of course, they could also have generic bonuses that makes them all around better or worse.

Some units perform better versus other types, where Chariots are good versus Light Infantry but bad versus Heavy Infantry.

And then the comparison of the combat tactics between the opposing forces.

The experience a unit has reduces how much damage that unit takes.

Then this damage is multiplied by a value to scale damage so combat lasts over a desired amount of ticks.

Combat Tactics
One of the more major difference-makers in combat is the tactics. For each army you can determine one offensive and defensive tactic, which each has 1 they are great versus, and 1 they are bad versus.

The offensive tactic is used if you are the ATTACKER in a battle, and the defensive tactic is used if you are not the attacker.


Offensive Tactics

All Out Assault
+30% versus Withdraw
+20% versus Probing Counter Attack
-20% versus Hard Defence
Both sides takes +10% casualties.

Frontal Assault
+20% versus Withdraw
+10% versus Probing Counter Attack
-10% versus Hard Defence

Outflanking Attack
+10% versus Strong Counter Attack
-10% versus Mobile Defence

Echelon Attack
+10% versus Mobile Defence
-10% versus Probing Counter Attack

Probing Attack
-10% versus Strong Counter Attack
+10% versus Hard Defence
Both sides takes 25% less casualties

Defensive Tactics

Strong Counter Attack
+10% versus Probing Attack
-10% versus Outflanking Attack

Probing Counter Attack
+10% versus Echelon Attack
-10% All Out Assault
-10% Frontal Assault

Hard Defence
+10% All Out Assault
+10% Frontal Assault
-10% Probing Attack

Mobile Defence
+10% Outflanking Attack
-10% Echelon Attack

Both sides takes -25% casualties.

Stay tuned, next week, Trin Tragula will be writing a bit about the game..
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ok, so we have a 2% damage per dice roll.
Now I wonder about the attack and defense stats of the units !

However, a bit too much EU4 like in the end. I would have hoped for large changes
Very nice, and like the battle window artwork
Will experience be possible to increase. EU: Rome casulties are so high and experience gain so low that it is pretty much impossible to get a high level of it, especially since the decay is brutal.
Isn't the withdraw -25% casualties to both sides instead of +25%?
Really nice that there are quality differences (discipline/experience) between units!

I’d personally like to see a bit more variation in available tactics, and having them effect the performance of certain unit types as well.
Looks good.

A few questions regarding Combat Tactics:

- Does the player decide the Combat Tactic before a battle, or is the Combat Tactic randomly allocated?
- Does the chosen Combat Tactic persist with the army unit after a battle (and into subsequent battles)?
- To what extent does the AI choose the Combat Tactic, does it take into account it's army composition and strengths?
Why do battles have to last for several days? That's not very plausible

I think it's like other Paradox titles where... like... it's not the actual battle that's lasting for several days (or even months in some cases), but the whole overall maneouvreing and engagement of the two (or more) armies.

Like the scouting, the marching, the shadowing, more scouting, more marching, some skirmishing, some withdrawing to find better ground, more marching, more skirmishing and finally... the battle.

But all of this is represented as a battle. So it's like an abstract.

Or something.