The focus is command and control — Can you devise a plan that will survive contact with the enemy?
If Only... is a grand tactical game of the Dardanelles Campaign in World War I. Most of the rules subsystems will be familiar to experienced players, although the terrain rules have a few interesting twists, and the Command rules are unusual. The Command rules aim to simulate the difficulty that large human organisations experience in reacting quickly and intelligently to changes on the battlefield.
It is important to remember that the British entered this campaign expecting to fight something like the Boer War. Although the fighting in France had stalemated a few months earlier, the Army in Egypt had very few officers with recent experience from that Front. The 29th Division was made up of ex-garrison units from around the empire, and the little experience of soldiering in the ANZACs was from the Boer War. Therefore they expected to fight fairly open battles of manouevre, with artillery firing over open sights in direct support of infantry advancing in waves. Riflemen were trained to fire as whole platoons at a single target under the direct control of their officer.
The sequence of play is chit-pull by Formation, typically brigade or regiment. A semi-randomly selected Formation moves in its entirety before the next Formation moves. The selection order is modified by an initiative die roll influenced by the degree of prior planning, the holding of key terrain features, and the current disorganisation of each army.
The movement rules are generally standard, although the close terrain and subhex occupation rules are novel and allow a small-scale map to model quite fine features. The subhex rules allow the entire peninsula from Suvla Bay to Helles to be printed on a manageable number of sheets, yet still allow for the complex interplay of ridges around Anzac.
Daylight turns are two hours long, therefore units have sufficient time to move around within their hex. Units do not have facing and can perform Opportunity Fire as many times as there are targets.
The turn structure is deliberately designed to hinder complex choreographed moves due to the difficulties of communication in World War I.
Combat is fire combat. Commanded Fire is deliberate coordinated fire against particular targets. Opportunity Fire occurs when a moving stack expends Movement Points within range of an enemy unit. Most units are rifle units with a fire range of one, therefore most Opportunity Fire only occurs when adjacent to the enemy (the exception being artillery). A key design goal is that Opportunity Fire should not slow the game down as much as it does in many World War 2 tactical games.
Assault is also fire combat, although at range zero and it continues until one side gives up or is destroyed. A special table is used that combines the statistical results of multi-round fire into a single roll. This table avoids the endless rounds of dice rolls required in many other grand tactical systems.
Machine guns are separated from rifle units for several reasons. Most importantly, that was the way the armies of the time were organised. The Ottomans followed the German pattern, locating MGs centrally within the infantry regiment, allocating them to particular battalions as the situation demanded. A battalion of the regiment might be allocated all the machine guns, or they might be allocated evenly. The British officially included their Vickers MGs within the infantry battalions, but within a day of landing all MGs had been informally collected at the brigade level and controlled centrally in the same manner as the Ottomans.
Artillery is organised as batteries. The various armies grouped the batteries into battalions, brigades or regiments, but all armies ignored these higher groupings during operations and commanded them as individual batteries. The Ottomans in particular would collect every battery in a region and attach it to the closest division, irrespective of the batteries' formal affiliations.
The Ottoman divisions each included a small cavalry squadron. The squadron operated as mounted infantry — they rode to combat, then dismounted and fought as infantry. The cavalry were used for reconnaissance in force, so there are no Napoleonic-style cavalry rules. Therefore these rules cannot simulate the Australian Light Horse's charge at Beersheba in 1917. Cavalry have been included because they were first reinforcements to arrive on the scene during the Anzac landings and had a material effect.
All armies commanded their infantry as groups of battalions — regiments of three rifle battalions for the Ottomans and French, and brigades of (usually) four battalions for the British. For special operations with long lead times (e.g. landings), smaller units could be given individual missions, but once battle was joined such fine-grained control proved impossible. Hence the standard command-element is the Brigiment (a contraction of brigade and regiment). To add to the confusion, the French had both brigades and regiments. In If Only... the French command by regiment, so the regiment is their Brigiment.
Formations are issued orders at dawn and then must follow them until they either succeed or fail. Failure is caused by casualties and friction. It is also possible to change orders during the day, depending on the command agility of the particular division. An optional set of rules simulate orders in greater detail.
The standard frontage of a battalion in the open was 800 metres — two companies forward and two in reserve. Hence the standard counter mix provides two half-battalion counters to cover two hexes. The provision of two counters is not just a counter-mix convenience, the British (at least) exercised with half-battalions just as commonly as companies in pre-war drill. The Australian 9th Battalion was allocated two separate half-battalion goals separated by several kilometres. During the initial landings battalions were often covering a front of 2km, hence the landing scenarios also include company counters. Battalion counters are included for convenience in crowded areas of the map, especially during the non-landing scenarios.
The Line of Sight rules have undergone many evolutions. The tactical situation at Anzac was governed by tiny ridges — too small to indicate on the map. The folded ground terrain type models these features and allows two opposing units to occupy opposite sides of the same tiny feature, just as they did in real life. Ridges are "military crests," i.e. significant changes in slope (points of inflection for the mathematically inclined). The ridge and Line of Sight rules are designed to be a compromise between accuracy and ease of play. In essence the Line of Sight has been pre-calculated onto the map by the designer so that the players do not have to perform any "rise over run" calculations. Remember that in reality the units were spread throughout a hex, not concentrated on the central dot.
These series rules are intended to cover the entire Dardanelles land campaign, but have been specifically tested on the first week following the initial landings in April.
The special scenario rules are in a separate booklet.