Reflections on Impetus

Impetus is my favourite set of ancient and medieval wargames rules. I have been playing it now for over two years but it is only since I joined the Sheffield & Rotherham club nearly six months ago that I have been playing it on a regular basis. Prior to becoming hooked on Impetus I have played Warhammer Ancients, DBA, DBM, and Field of Glory. This blog will be about why I like Impetus, including highlighting some limitations.

I wish to start by saying what it is that makes Impetus the best set of ancient and medieval rules I've played. They are fun and produce a reasonable simulation of how I imagine an ancient battlefield. Like my favourite set of Napoleonic rules, Grande Armee, Impetus combines a units morale and fighting capability into a single value, it's VBU.


Impetus, as it's name suggests, is all about grabbing the initiative and maintaining momentum. The impact bonus units receive from charging encourages armies to press forward and the follow up combat mechanism can mean that a unit which begins to get pushed back and quickly be rolled over if it's opponent can follow up.

I like the look of the game, a unit looks like a body of men even when on it's own. The game mechanisms are simple and yet subtle. While it is possible to quickly march a large portion of your army across the battlefield, this is done at increasing risk of disordering the troops and the army being scattered piecemeal across the field. I like variability in the game and the initiative system in Impetus means that the order commands move in can vary each turn.

There are however a few issues with the rules that I think should be looked at and are potentially easily fixed. While I will spend more time discussing these in this blog I want to stress that the positives of Impetus monumentally outweigh these elements and it is my far the best set of rules for the period I have played.

Break point

In Impetus each unit has a VDU factor from 1 to 3 that represents the morale contribution that unit makes to the army as a whole. For example, a Legionary unit has a value of 3 whereas some skirmishers have a value of 1. A Command breaks at the end of the turn it loses 50 per cent of VDU, and an Army breaks at the end of the turn when it loses 50 per cent VDU.

The fixed break point of 50 per cent has two distorting impact so the game which I believe distort historical reality.

First, as each player is able to determine how close they and their opponent are to breaking, the result can be perverse behaviour as players chase individual units to knock the enemy over the break point rather than focus on the battle as a whole.

Secondly, it is beneficial to form an army into a single command as it has more staying power. An army in a single command must lose units up to 50 per cent of it's VBU in order to break. Dividing an army equally into two commands reduces it to a 25 per cent break point, as either half going would result in the whole command going. Though it does extend the command range making it easier to maintain order and manoeuver. Most armies were divided into multiple commands especially in the medieval period and the rules should encourage this.

The solution I propose is to have a system that starts to test whether an army breaks once it has past a certain threshold, for example 40 per cent. The test is based on the proportion of the army beyond that threshold and the length of the game. By not having a guaranteed break point players must focus on inflicting the most damage possible on the enemy at all times.

Strength of firing

There have been a number of situations where firing from skirmishers has almost overwhelmed heavy infantry but the new rules in Extra Impetus 3 may have resolved this.

Roman lines

As mentioned in my last post the exchange of Roman lines is to difficult, with only a 1 in 4 chance, and is limited to the Polybian period only between Hastati and Principes. I could go on for quite a while on this one and plan to do a future post drawing upon some current reading so for now I'll simply state that I believe that the exchange of lines needs to be easier and should be extended to late republican armies.


Scale

I want to finish this post with a quick comment on scale. I normally play the game in 15mm but recently participated in a 28mm tournament at Derby. The different scales do impact on how the game plays. The larger movement distances mean that there is often less opportunity to shoot though this is impart compensated for by larger shooting distances. 28mm certainly feels more hectic with less opportunity for initial manoeuvre.