The Arts of War:

1. Cavalry in Defense
Cavalry are somewhat of an unknown quantity to some of even the most experienced players of Sid Meier's Gettysburg!, and I don't find it surprising because most people only use them in the First Contact scenario and Longstreet's charge around the Union flank at Round Top, I have included three scenarios to help with this lack of knowledge of Cavalry vs. Infantry and Cavalry vs. Cavalry, one comes from the scenario pack I produced a long time ago, Alternative Gettysburg.
Before you start you should remember to use Cavalry's great advantage, speed. You can run rings 'round infantry, quite literally! Cavalry vs. Cavalry Getty82.scn, A cavalry vs. cavalry skirmish where Gamble and Merrit have to hold off Fitz Lee and Hampton. Union: 2913 Cavalry. Confederate: 3495 Cavalry. The rebels have more and better-trained men but when played right, even on Lee/Hancock, Prudent/Flexible the skirmish is a piece of cake for either side. It is best to remember that Cavalry receive bonuses when they are in Skirmish formation, one is that they do not 'get stressed' when you move them, another is that Skirmishers (Infantry and Cavalry) do not block each others field of fire so they can fire through each other. One more thing to consider is that they don't get any bonuses when they are in line formation. They do not receive support blocks and their fire is less effective than infantry fire, also they don't have the staying/charging power of Infantry. Therefore Cavalry is more effective in skirmish line. As it doesn't matter how close the regiments are you can place them on top of each other to form a kind of Hornet's Nest.
AI can't handle this and generally forms up in Line, the AI has been configured that when in Line you charge skirmishers so the AI does that, only Cavalry in Line cannot charge Skirmishing Cavalry so they die really easily. But remember this, this tactic only works against other Cavalry and is rather pointless against infantry.
Now that is the genuine score on Longstreet level, prudent and flexible.
 Now look for the Yankee body sets, maybe one or two… Cavalry vs. Infantry:   Getty83.scn, A Cavalry vs. Infantry skirmish where Buford's division holds off Johnson's Division while falling back across the whole length of the map. Union: 5945 Cavalry, 589 Artillery, Confederate: 5996 Infantry, 358 Artillery, This scenario is actually not from the scenario pack and was cut out because I didn't need it, I think it's fun just the same because very seldom do you have so much room to work with while using so few men. If you do use a defensive position to try to hold off Infantry in Line, pick the position carefully.
This is really a very easy one for the North to win against the AI, just put your men in Skirmish and on fallback and rearrange them from time to time when a worrying gap appears. Try to keep contact with the enemy at all times while falling back. This inflicts far more stress on them than it does on you. Use intermediate defensive positions to hold the enemy up and to inflict some casualties on them but retreat before you are overrun.
'Cavalry cannot stand up to Infantry, against a real attack they'll run quicker than hell and your line will crumple.' This is actually a load of old crap, Cavalry will hold until hell freezes over if placed right, try the scenario below to see what I mean. It turns out that cavalry are actually better than Infantry, shocked? So was I, I believe that you will be amazed at the staying power of correctly placed (on a tree line etc…) cavalry. Attempting to hold a single VP using Cavalry alone against Infantry is easy, but you've got to expect to have to fall-back more than when using Infantry and to make more use of reserves. An interesting example of this is a scenario I adapted from getty83.scn up there, I'll not bother to go over this one, as I don't think you need me to. But you can just play it and see what you can make of it. It's got the same numbers as the scenario above but is fought in two variants, Cavalry Defends and Infantry defends. I simply swapped over the positions. Getty29.scn

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