Once you've got a good understanding on how to defend a firebase, it's a good idea to split your forces in two and deploy a firebase on either corner of your deployment zone. Doing so means your enemy now has two firebases he needs to take out, rather than being able to focus all his power onto one. Due to the range and mobility of Tau weapons, the firebase can actually work together and support one another. The important thing is to set up your forces so that each unit can target the majority of the board. As you set up consider the weapon ranges. Missile Pods and Plasma Rifles should set up closer to the center, while Broadsides can be as far away as you like. Piranhas are set up in the middle of the board so they can support either firebase depending on your opponents avenue of approach. Click the image below for a diagram of a dual firebase deployment.
If set up well, your opponent has a couple choices. He can decide not to advance and instead out-shoot you. Guard and some Krak-Missile Spam Space Wolf Armies will try to do so. The good thing is your getting plenty of cover saves from your Kroot Screens and you have plenty of firepower to throw back at him.
GW has made most of the popular armies close-range fighters so the enemy will most likely choose to advance. There are a couple ways he can do this. He can focus on one firebase and throw everything he has at it. Once it is destroyed, he can then turn to face your other firebase. If you're unlucky enough to have a big piece of terrain directly in the center of the board blocking line of sight (like on every table at the NOVA Open), this is the best option for the enemy. He can use the terrain to limit one firebase's shooting. Because of the Tau's mobile firepower, he will still face the majority of your firepower before he can connect with your forces at close range. Don't forget the lessons from the last article, use your piranhas and drones to block his advance as much as possible.
In an ideal world however, you'll be set up for a pincer move. One firebase takes the brunt of the attack, throwing piranhas drones and kroot to block his advance, while the other base swings around to pour firepower into his side and back. The idea is to bring the power of your entire army onto his attack.
Alternative, the enemy can split his forces and choose to engage both firebases at once. This is very nice for the Tau because you can use piranhas to block the advance and then use the fire power from the opposite firebase to hit side armor and minimize cover saves from intervening models. Your Broadsides, instead of firing at front armor that is advancing on them, fire on the side armor of vehicles advancing on the other firebase and vice versa. Piranhas as always move out to block and defend. Here I've got three units of piranhas, two get committed to blocking the enemy while the third moves up a little to the center, ready to pounce and melt something the next turn. Click the diagram below to see how the crossfire works.
Either way, because of the Tau's range and mobility, the enemy will be facing your entire army's killing power at once. This is particularly effective against small elite armies like Space Marines, Blood Angels and Daemons. It's more difficult against Imperial Guard and Space Wolves because their armies are larger and typically carry more shooting. Eldar have trouble dealing with this set up as well, because it almost negates their speed advantage because wherever they move, you have a unit that can shoot them.
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