Crossfire’s Moving Clock and Variations

Hit the Dirt introduced the concept of the Moving Clock to Crossfire. I’ve done an Analysis of the Moving Clock, dreamed up some variations on this concept (Turns, Minutes , Clock ticks), and noted some thoughts on modelling the moving clock.

Example of the Moving Clock

Here is an example of the Moving Clock rule from Hit the Dirt. It is based on the one in Cassino Massift scenario from HTD:

Special Rule 4: The Moving Clock is in use. The scenario starts at 0600 and ends at 1800. The clock advances 30 min on 5+ on one die, rolled at the end of each defender initiative. The attacker gets reinforcements at 1200 and 1230 hours.

Modelling the Clock

You can just write the time on a piece of paper. But that is a bit dull. So I use an alarm clock without a battery. Happens to be camouflaged. Obviously because it doesn’t have batteries the arms only move when I turn the dial; every time the moving clock advances in the game I manually advance the hands on the clock.

Jakim Friant has an even more interesting solution … he scratch built a Clock Tower. See Little Soldiers: Clock Tower for instructions.

Analysis of the Moving Clock

I wanted to know how long a typical Hit the Dirt game was. Simple question; complicated answer. The following scenarios use the Moving Clock. There is enormous variation in the nominal game duration (from 3 hours 15 minutes through to 13 hours) and in the average number of defender initiatives this time corresponds to (from 20 to 75). And there is no direct correlation between the duration and the average number of initiatives as the moving clock tick also varies, both in number of minutes (15 to 30) and probability (either 4+ or 5+ on 1d6). Each initiative nominally corresponds to between 5 and 20 minutes, although 10 minutes is the most common.

Possibly the best illustration of this is the Battle for Hardt scenario and the Debacle at Hitdorf scenario. Both take 39 defender initiatives on average, but one scenario has a 13 hour duration and the other is over in 3 hours 15 minutes. By chance these are the longest and shortest games in Hit the Dirt.

Scenario Duration Tick Ticks in Game Defender Initiatives per Tick Average Defender Initiatives Average Minutes per Initiative
HH MM MM 1d6
Roadblock on Highway 120 03 20 20 4+ 20 2 20 10
Reconnaissance Before Pontecorvo 06 00 30 4+ 12 2 24 15
Assault on Tula 04 30 30 5+ 9 3 27 10
Deadman’s Moor 04 30 30 5+ 9 3 27 10
Hotel Brittania 08 00 30 4+ 16 2 32 15
Scottish Corridor 05 30 30 5+ 11 3 33 10
Bocage 05 30 30 5+ 11 3 33 10
Battle for Hardt 13 00 60 5+ 13 3 39 20
Debacle at Hitdorf 03 15 15 5+ 13 3 39 5
Germans in the Woods! 10 15 30 4+ 20.5 2 41 15
Dung Farm 09 00 30 5+ 18 3 54 10
The Island 06 20 20 5+ 19 3 57 7
Monte Altuzzo 10 30 30 5+ 21 3 63 10
Cassino Massif 12 30 30 5+ 25 3 75 10
Average 06 30 30 5+     39 10

So what can we learn from this? Well, perhaps not a lot, but there are a few observations:

• The average nominal scenario duration is 6 hours 30 minutes.
• Each defender initiative is nominally about 10 minutes.
• 5+ is the most common probability for the Moving Clock ticking over.
• 30 minutes is the most common duration of a Moving Clock tick.
• There are on average 39 defender initiatives per game, although this varies a lot.
• Even if your nominal scenario duration is more or less than 6 hours 30 minutes, then the other variables are still usually the same.
• Only in exceptional circumstances would you use a shorter/longer clock duration or use 4+ instead of 5+ to trigger a clock tick.

If your scenario fits the standard profile, then your life is simple:

Special Rule 4: The Moving Clock is in use. The scenario starts at X hours and ends at X + 6.5 hours. The clock advances 30 min on 5+ on one die, rolled at the end of each defender initiative.

Variation 1: Turns

Other game systems – such as Advanced Squad Leader, AK47, and Rapid Fire – use turns. This variation of the moving clock makes converting scenarios from those systems much easier.

Example from a scenario:

Special Rule: Turns are in use. The Clock advances one Turn on 5+ at the end of each initiative of the Defender. The game ends after 24 Turns. The attacker get reinforcements on Turns 12 and 13. Each Turn is nominally 30 min.

Preparation

Calculate the number of Turns for the scenario. This is the elapsed time in minutes divided by the amount of time the clock can advance when the clock die roll is met or exceeded.

For example, in “Cassino Massif” the game starts at 600 and ends at 1800; this is 12 hours or 720 minutes. The moving clock advances 30 min on 5+ so there are 24 Turns in the scenario.

You’ll also have to calculate on which Turn any special events occur. Calculate these in the same way, but using the time of the special event instead of the end of the scenario.

For example, in “Cassino Massif” the Germans get reinforcements at 1200 and 1230. These are 6 hours (360 minutes) and 6.5 hours (390 minutes) into the scenario, which corresponds to Turns 12 and 13.

During play

During play this system is simple. At the end of the defender’s initiative throw for advancing the Moving Clock as normal. If the score is met then the clock advanced one Turn. Special events and the end of the scenario occur as per the numbers you’ve prepared.

Variation 2: Minutes

This system comes out much the same as the Moving Clock of Hit the Dirt, but ensures that time progresses each initiative, rather than occasionally leaping up in fixed amounts. Scenario events (start, end, reinforcements) still happen at the times given in the scenario.

Throw 1d6 at the end of the second player’s initiative and multiply by a scenario specific factor to give the number of elapsed minutes.

Hit the Dirt Multiplier Average Clock Movement Type of Game d6 Option
15 min on 5+ 1.5 5 min Intense fire fight in good weather 1d6+2
15 min on 4+
20 min on 5+
2 7 min 2d6
20 min on 4+
30 min on 5+
3 11 min 3d6
30 min on 4+ 4 14 min 4d6
60 min on 5+ 6 21 min 6d6
60 min on 4+ 9 32 min In lousy weather 9d6

Example: In the Hit the Dirt scenario “Cassino Massif” the clock advances 30 min on 5+, you would use a multiplier of 3. So at the end of the defenders initiative throw 1d6 and multiply by 3 – this is the number of elapsed minutes, e.g. if the defender throws a 2 on 1d6 then 6 minutes pass.

I tried this once but got confused when multiplying the die score, so invented the next variation to make my life simpler.

There is another variation on this that might work. Just throw the number of dice shown in the “d6 Option” column. In one case (1d6 + 2) this needs a modifier.

Variation 3: Clock ticks

Example from a scenario:

Special Rule: Clock ticks are in use. The Clock advances 1d6 clock ticks at the end of each initiative of the Defender. The game ends when the Clock gets to 240 ticks. The attacker get reinforcements after 120 clock ticks and again after 130 clock ticks. Each clock tick is nominally 3 minutes of game time.

Basically at the end of the defender’s initiative 1d6 is added to the Clock; when the Clock reaches a certain number special events occur, or the game ends. It is important to note that each “Tick” on this clock corresponds to a number of minutes. For example, the German player might throw 3 at the end of their first initiative; this corresponds to 3 clock ticks. A 6 at the end of the second initiative means a total of 9 clock ticks have passed.

Conversion from Hit the Dirt

If you’re converting from Hit the Dirt style Moving Clock then do this

Step 1: Calculate the number of clock ticks for the scenario. This is the elapsed time in minutes divided by the Divisor from the table below. (Effectively each Short Clock Tick equals the Divisor in minutes.)

Hit the Dirt Divisor
15 min on 5+ 1.5
15 min on 4+
20 min on 5+
2
20 min on 4+
30 min on 5+
3
30 min on 4+ 4
60 min on 5+ 6
60 min on 4+ 9

For example, in “Cassino Massif”:

the game starts at 600 and ends at 1800; this is 12 hours or 720 minutes. The Divisor for this scenario (30 min on 5+) is 3, so the game ends when the Clock gets to 240 ticks.

Step 2: You’ll also have to calculate on which clock ticks any special events occur. Calculate these in the same way, but using the time of the special event instead of the end of the scenario.

For example, in “Cassino Massif” the Germans get reinforcements at 1200 and 1230. These are 6 hours (360 minutes) and 6.5 hours (390 minutes) into the scenario, which corresponds to clock ticks 120 and 130.