As I stated in my first article about the Sisters of Battle, Immolators have been getting a lot of bad credit for being overpriced and generally too easy to kill to be of any use. My hope is that this article will change your view, and hopefully teach you on how to use this very fluffy tank.
First of all, using the Immolator as a troop transport is generally a bad idea. Taking it as a transport is fine, as long as you don't transport anything in it. This will enable you to take Immolators while keeping all the Exorcists and Retributors allowed by the force organisation chart.
The most appropriate unit to attach an Immolator to is most likely a squad of Celestians. Whereas Celestians aren't that great to begin with, a squad of five will give you an extra faith point and a Heavy Bolter (in theory optional, but in reality mandatory). If you play pure Sisters of Battle, you are likely to have few elites, if any at all – and thereby you can usually take a squad of Celestians with little problem.
Also, you can attach the Immolator to a small squad of Dominions or Retributors. Finally, you can always just take it as a Heavy Support choice, and it has its upsides as well, which I will get to later in this article.
Weapons and upgrades:
Usually, the best thing to do is to stick with the Twin Heavy Flamers. They are awesome for taking out hordes of infantry – especially those with a little lighter armour, flushing out things from cover and generally harass your opponent's squads.
Personally, I've had a good deal of success with a Heavy Bolter Immolator that used Blessed Ammunition to pick off squads stuck in cover from afar. It will not completely destroy an entire unit by itself, but it can pretty easily force a morale check on creatures with toughness 3 and a save of 4+ or worse. Regardless if they pass or fail, you'll at least have some fewer irritating infantry models squatting in cover to worry about. This is of course especially good in a Sisters of Battle force, because they lack good long-range firepower other than the Exorcist.
For other upgrades, always take Extra Armour and Smoke Launchers. Other than that, you'll waste points and be disappointed in most cases.
Speeding and flaming:
The Immolator with the Twin Heavy Flamers has a very neat little special rule that allows it to move at full speed and still fire. Because Sisters of Battle are such an unusual army, your opponent is likely to not know this, and the Immolator will thereby provide a great surprise for your opponent, while you can flame away with good results, due to the re-roll provided by the "Twin" in "Twin Heavy Flamers".
Also be careful how you place the template. The rules state that the template must be placed on the edge of the base of the model, covering as many enemy models as possible without touching any of your own. Think about that, and remember that the base of the Immolator (and all other tanks) are the hull.
One of the best uses for an Immolator is to be a fire magnet and a wall for your Seraphim, Rhinos and similar.
The strategy is relatively simple – you pick one of your units that is either valuable or fragile (or both), deploy that unit behind the Immolator and use the Immolator as a moving hill or wall and keep your more valuable unit out of sight of your opponent. Smoke Launchers and Extra Armour will keep the Immolator alive and moving hopefully, at least until you can get into range with the unit or tank that you are protecting. This will usually be a squad of Seraphim or a Rhino, which means they will reach the enemy by turn two. '
The Immolator can be pretty good as a supporting vehicle as well. Tool it up with a pair of Heavy Bolters, Blessed Ammunition and Extra Armour. If you have the points to spare, you could also give it Smoke Launchers, but I doubt that they will be very useful.
Simply place the Immolator far in the back and use the Heavy Bolters that are now ignoring cover saves to pick off small enemy units stuck in cover. Because of the relatively low threat level of the vehicle, it will be a low-priority target for your opponent. This will enable it to fire most of the turns in a game, and thereby pay for its points.
I will finish this article with saying that Immolators in no way are awesome tanks. They will barely pay for themselves in most games. They are dancing on the fine line of "useful" versus "not useful/overpriced" which is also true for a lot of other Witch Hunters units.
Still, it is a very cool unit – and while they may not make a list intended for a tournament, they will fit right into a list intended to play against your mates or regular group.