The ‘Alan Roll’ is a method of randomly determining the occurrence of a particular event in a game. It is primarily used to determine the appearance of off-table troops such as reinforcements or flank marches, but can easily be applied to other events as required.

Although dubbed the ‘Alan Roll’ by other members of the Staines Wargamers, I don’t claim to have originated the technique. It owes something to the E.D.N.A. (Ever Decreasing Number Allocation) system described in an ancient copy of Miniature Wargames, and is so simple that it must have been used before.

In general there are four basic methods of determining the appearance of reinforcements:

• Reinforcements appear on Turn x. There is no randomness in this method and allows advanced planning based on their appearance.
• Reinforcements appear on Turn x, where ‘x’ is a random number. This fixes the turn the reinforcements appear, so the player can plan based on this knowledge.
• Reinforcements appear on a given roll. This is the method used by DBM to determine the appearance of flank marches. They appear on the turn after the owning player rolls a ’6′ on a D6. This method makes their appearance unpredictable, but the time frame in which the reinforcements appear is very variable, perhaps making them too unpredictable. It is possible that the reinforcements will never appear.
• Reinforcements appear according to an increasingly easier random roll. This is the method whereby they appear, for example, on a ’6′ on turn 1, a ’5′ or ’6′ on turn 2, a ’4′, ’5′ or ’6′ on turn 3 and so on, generally reaching a point where they automatically appear.

What I tried to achieve with the ‘Alan Roll’ is a method of making their appearance of reinforcements unpredictable, but allowing them, on average, to appear around a certain time.

The method is this:

The likelihood of the reinforcements appearing should be expressed as a number. On each turn the owning player rolls a dice and adds the score to the total of previous rolls. If the score exceeds the predetermined number then the reinforcements appear. Simple.

Determining the initial number should be based on roughly when the reinforcements are expected to appear, and what type of die is going to be used to test for them. Work out what die is going to be used, and determine the average roll possible; a D6 averages to 3.5 for example. Work out roughly on which turn the reinforcements should appear, and multiply the average die roll by the number of turns.

Example: In a game it is determined that a flank march will appear at some stage. It will be tested for using a D6, and will appear around Turn 10. This gives and ‘Alan Roll’ number of 10 x 3.5 or 35. The reinforcements will appear when the accumulated total reaches 36 or more, which means they may not appear until Turn 36 or may appear as early as Turn 6, but on average will appear around Turn 10.

Obviously the spread of the possible turns on which they appear depends on the type of die used. A D10 will give a wider spread of turns than a D4 for example. I try to use whichever die is appropriate for the game; ‘Fire and Fury’ only uses a D10, so I use a D10 for all ‘Alan Rolls’, the DBA system is exclusively D6 based. However this is a matter of personal preference. It is possible that the die used could vary during the game based on battlefield circumstances.

Example: In a game which uses command points to move troops (such as DBA or ‘Principles of War’) it is decided that points can be spent to ‘hurry up’ the appearance of reinforcements. A basic D6 is used for the ‘Alan Roll’, but this is changed to a D8 if one command point is spent, and a D10 if two are spent. Thus the commander can speed up his reinforcements at the expense of decreased control on the battlefield.