Ah the Fire Prism, the glorified laser pointer of the Eldar codex! Since this is actually a pretty iconic tank for the Eldar that finds its home in many lists, I wanted to touch on what makes this tank so good and what some of the best uses for it are.
For those that may not know, the Fire Prism is a 12/12/10 fast, skimmer, tank with the options for all of the Eldar skimmer upgrades. The main deal with this tank, however, is the Prism Cannon which is a 60" S9 AP2 small blast or a S5 AP4 large blast at BS 4. The Prism Cannon also has a unique feature allowing it to be "linked" to another Fire Prism's shot, increasing the S by 1 point and lowering the AP by 1 point and twin-linking the shot. This is why you usually see or take at least 2 Fire Prisms in an army and where you get that mentality of "take at least 2 Fire Prisms or don't take any at all". With all of that said, the Prism Cannon can be an overpriced lascannon/whirlwind if it isn't shooting at the right targets but when using the gun on the right targets it can result in your opponent simply removing models or squads from the table.
Are tanks the best target for a Fire Prism?
|Fire Prism's rarely accomplish this =(|
While the Fire Prism does have a very appealing antitank capability with a S9 AP2 blast shot (S10 AP1 when linked with another Prism), I don't feel that the Prism Cannon is primarily an antitank weapon. I say this because in the end, you only have 1 shot from 1 source that has to pass through a series of rolls that could let you down at any given time just to maybe kill or disable a single tank which belies the true power of the Prism Cannon IMO. From the scatter roll, to the armor pen roll to the damage table, the odds (at least my odds) show me that I'd be better off with just using a Bright Lance, Eldar Missile Launcher or some Fire Dragon shots to take out that armor that my S6 Scatter Lasers and Shiruken Cannons can't handle.
Infantry, shoot them dead!
|Fire Prisms like shooting at infantry!|
Each mode of fire from the Prism Cannon offers the perfect tool for killing any kind of non-vehicle units so I would argue that the Fire Prism's prime targets should be something with a T value. The S9 AP2 blast, for example, is great for any 2+ save or FNP toting models and will likely instant kill any ICs or multiple wound models that fail any saves they might have. The S5 AP4 shot is perfect for taking out horde units as they will generally be wounded on a 3/2+ and get no armor saves. When you add in another Fire Prism to the mix, you now have the capability to throw down a S10 AP1 shot for any of those rare T5 multiple wound models that will give the rest of your shooting a headache or you can throw down a nice S6 AP3 shot for taking out bunches of Space Marines.
Some general tactics:
Now of course, when your opponent spreads out or is in cover, you won't get as much bang for your buck but there are ways to lure an enemy to bunch up or get out in the open. One way to do this is to put a vehicle of yours out there in charge range of an enemy unit, perhaps one with Fire Dragons in it, that the enemy will be tempted to charge. If they do charge it, they will be bunched up and if your tank survives just zoom off and now you have a bunched up squad of guys in the open. If they kill the tank, they are still in the open and with the proper angle the unit should get no cover from your shot. Another way to do this is by killing their transports where the guys will naturally be bunched up after disembarking and again, with the right angle of firing, you can very realistically get a shot off on the unit such that it won't get a cover save. Lastly, you can always place objectives in the open forcing the enemy to be in the open if they want to claim or contest those objectives therefore ensuring that they will get no cover if they want to go there. In hindsight, another option could be charging a unit with harlequins and on their turn (so you have the next turn to shoot at the previously engaged unit and even charge again) hit and run out of the combat so the enemy only has 3" to move around which probably won't be enough movement to spread out adequately from a Prism Cannon shot.
Save the shot for when you need it:
So with all of that said, I have found that I end up saving my Fire Prism shots until the end of the shooting phase to see where they can make the biggest impact and if there isn't a really good shot at infantry models, I will take a shot or two at a tank that I particularly want destroyed. Fritz from Way of the Saim Hann made a pretty comprehensive youtube video using Fire Prisms that you guys can check out as well. That pretty much covers the Fire Prism so If you guys have anything to add/say or if I missed anything feel free to comment!