Decisive Action: Envelopment

My crudely drawn diagrams will eventually get better, I promise.

All of you experienced veterans of Belegarth are well aware that full encirclement of an enemy force is extremely rare and hard to pull off in our game. The scale is too small, allowing each person greater awareness of the big picture. The forces are generally too evenly matched in skill and numbers for one side to have enough of an advantage to attempt such a difficult maneuver.

The only time we usually see full encirclement is during the cleanup phase of battle. Well after the decisive action, a group of mobile fighters will encircle a group of wounded (legged) opponents. Not exactly as epic or decisive as the Battle of Cannae.



Source: The Department of History, United States Military Academy.  Copied from Wikipedia.

So why talk about it? Because a smaller scale of it happens all the time. One of the most useful tools in a commander's playbook is the kill pocket. The simple change in formation requires a few fighters to step back off of the line, forming a U shape. Any enemies inside the U are easy targets, even if they aren't fully encircled. Kill pockets are widely used to defend bridges and castle entrances, or to attempt to lure support weapons into the trap.

The reason a kill pocket works, is because those in the middle have to fight against three directions. It is nearly impossible to defend against spears and support weapons coming from both sides and the front, let alone deal with the shieldmen protecting them. By concentrating their attacks towards the middle, those using the kill pocket can cut a hole through the enemy line, causing a major breakthrough.  Of course, in the open, those on the top of the U are somewhat more exposed and must defend themselves from opponents on two sides--those inside the pocket and those in front of them.  It is important for those fighters to fight defensively and keep the edges of the pocket intact, otherwise the enemy might take advantage of this weakness and push against them.

On the open field, wise commanders will spot the trap, and either pull their forces out of the kill pocket, or deploy shock troops and reserves to press into it. If that second option sounds dangerous, that's because it can be. Depending on the composition of the pocket, sometimes those at the bottom of the U are stretched thin enough that a burst of shock troops can break through. This is extremely effective when the defenders don't have reserves, allowing your team to press through the pocket and roll the enemy flanks from the center in a major breakthrough.

Source: Crudely drawn diagrams.  Blue dots are standing in for attackers (aka, the good guys).

Another fairly common sight is aggressive or heavy flanking forces rolling around a flanks, causing the enemy wing to bend backwards. Usually, it is preferable to have the wing extend to stop flankers, but a strong rush of them is often enough to force the wing into the defensive. In extreme cases, the line will curl backwards on itself enough that the main line and wing are standing nearly back to back. At this point, even if they aren't fully encircled, the defenders are going to be cut down in short order.

For the defenders, their first option of extending the line gone, need to choose a new plan quickly. Everyone that will soon be encircled can fall back, reforming a shorter, stronger line and fight the flankers. This will sometimes work, but it requires those on the wing and core to be aware of the danger early. The other option is to pressure the opposite flank hard, ideally bending it back in equal measure. This causes the two lines to rotate around the middle and allow the line to reform before being crushed. Of course, they'd have to act quickly to overcome the challenge, otherwise the center may not have enough time to escape.

More Dots!  Blue dots are trying to salvage the line and regroup against a strong enemy flank.
 

In general, try to keep your own line strait across the field.  When you need to add a bend to your line for any reason, try to make sure that you are causing the enemy to fight against multiple directions without exposing your backs--don't curl back upon your own line.  Kill pockets are useful, but do have weaknesses on the edges.  Try to use them more when the enemy has to come through the middle.  For those newer fighters, instead of retreating back behind your line, try spreading out away from them--maintaining decent spacing.  Your team would much prefer it if you didn't escort the enemy into the backfield as you retreated.