In list building, we can make lots of decisions to decide how the flow of the game will roll out. Astra Militarum is an excellent example of having access to variable speeds and board space within an army. We will describe a pure gunline, tank-heavy army as a "fast" army. It needs to kill fast and win fast. Every tank that drops is a significant loss in output, and we have nothing to give our opponent a reason to stay away from our lines. We can't slow the game down. So let's alter the list to give us some options to slow the game down and manage space. The most popular option is with a big unit of Bullgryn. To include them, we needed to drop some of that firepower, slowing our game as well, but we now have options and answers to a host of things we didn't before. Our game plan has become more dynamic, and the quantity of actions we have access to has increased. Now, I'm not saying that either of these builds is better than the other. They simply require a different pace to play.

So far, we have mostly talked about what we are playing and the pace it requires to be successful, but let's talk about how we can affect the speed of the game by affecting the opponent's army and game plan. As a Tyranid player, I am usually affecting my opponent's decisions with combat. My lists can rarely outshoot what I'm up against, but I can limit my opponent's shooting with Genestealers. I don't have to outshoot every turn if I can turn half of my opponents shooting off on the first two turns. In these scenarios, I'm trading out models for victory points and tempo. My 'stealers will routinely trade out point for point horribly. Killing some fodder out front and then touching tanks in behind. But this relates to a lot of the points mentioned above. The 'stealers have ramped up the actions allowed in my turn by a considerable amount. This decision may have only killed 40 points in guardsmen, but it also may have achieved a Recon or Behind Enemy Lines point, hold more, gained the bonus objective, and stopped a host of return fire. This move, of course, has slowed the game down in the sense that I've turned off their superior shooting, allowing my shooting to start leveling the playing field, but it may also have slowed the game down by preventing an aggressive unit of theirs from pushing forward. Something they may have wanted to do was push a Bullgryn unit forward to eat up space and get towards my gunline, but now it is forced to stay in its zone and get rid of the 'stealers. This action may unfold into all sorts of decision-making opportunities like my heavy weapons being able to remain stationary rather than falling back from the advancing Bullgryn. My opponent's slowed killing power allows my inferior heavy weapons to keep up, and their ability to take up space and dictate where I can be is changed as well.