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Rork
June 29th, 2007, 21:55
I thought I'd give a quick overview of one of the important elements an Eldar general needs to consider - controlling the table. Controlling the table isn't just about holding the right pieces of terrain or minimising enemy fire power while maximising your own.

It's also about geometry and angles.

Raw firepower alone won't always win the game, particularly against enemy vehicles whose armour is often difficult to crack with the average Eldar heavy weapon (being S6), usually meaning your decent AT weapons are few in number. While I'll be looking at fire prisms here, much of the general advice extends to missile launchers, bright lances and pulse lasers also.

In my experience, refusing a flank is the way to play the new, fast Eldar. Straight, fair fights on a wide frontage will almost always suit the enemy army more than it does the Eldar. Never play fair, play dirty.

Today I'll be looking at an abstracted example of how to use the enemy's weaknesses against them while maximising your own strengths - primarily those of speed and manoeuvrability.

Consider the setup below:


The green triangles are tooled up fire prisms, the red rectangles are lascannon/heavy bolter predators and the red square is a tactical squad with a lascannon.

Both sides are playing cagey. Both players know that a prism cannon or lascannon is going to knock out a significant amount of their firepower, so are hiding as a result. Typically the Eldar are outnumbered and outgunned.

(If this were a "live" game, one fire prism would be back up by most of the Eldar army, the other backed up with 1-2 small units at most)

But the Eldar are lucky, and go first.


The fire prism on the left would always be dangerously exposed if it had crossed the building in front of it. In the worst case scenario, it's likely that all three lascannons could have been bearing down on it. Not good. But in a six turn game with a 24" move, does it matter? Course not. In a flanking strategy, the waiting game is usually necessary before you can control one side of the battlefield.

You'll have to expose one prism, so it's up to the right hand side one to stick its neck out. The linked shot has a reroll to hit and penetrates a predator on 3+. It really doesn't stand much of a chance vs that sort of firepower, so gets taken out by a focused shot. When it comes to prisms, those angles I mentioned are important. The 60" range and the ability to combine shots means you've got to be able to use terrain to support your own tanks as shown above. Having a shot effectively travel 120" as it bounces from one prism to another won't be unusual!

The Imperials, of course, aren't going to let the Eldar have it their own way. The remaining predator could move to the right, but then it's severely out on a limb vs a fast and long ranged opponent. Moving right would likely mean the left hand fire prism will be able to stay out of lascannon range.



So left it has to be. Sensibly, the Imperial player is hugging the wood to present his front armour to the prisms. The lascannon unit opens up on the right-hand prism and shakes it (Love those holo-fields :D). If the predator is lucky, it might manage the same feat on the left hand prism.

Six turns and a 24" move? Hide. You've collapsed one space marine flank, so now is the time to use it. The left prism gets over the table while the shaken one hides. The left-hand prism is safe, and the right hand one can't be seen. In your average game, the imperial units would try to engage other units. That's where support units (particularly for the left hand prism) can come in.

Remember that prisms and falcons (as well as units like shining spears or warlocks) are your "king pins". Give your opponent something to shoot at that would be to his advantage to destroy (such as a vyper) but not necessarily important to you winning the game.

With the predator in a decent firing position, there would be little need to move it (Something I will revisit soon). Of course, the Eldar have had to deal with the first predator the hard way. But why should it be hard? High speed and high strength weapons makes many of your units a huge threat to side armour values.

Which brings me back to the angles. Very few vehicles are square. Most are rectangular, and have a lower side armour than front armour. This means their front 'arc' is quite narrow while their side 'arc' is quite large. And importantly means you really don't need to be square on to the side armour to lay on the pain.



The fire prism on the left dives out from behind that wood, while the one on the right hops straight over the building it was lurking behind (Love those skimmers). Once again, you've controlled your own angles so the prisms can see each other, but the predator would have difficulty getting at the right hand prism if it lives (the enemy might be tempted to split their firepower).

So boosting up the right hand prism gives you a near-guaranteed penetrating hit on the side armour of that predator thanks to the usage of angles. You're in the side arc just enough to get at the weaker armour and avoiding the tougher front armour.

Bang! Another predator.

Of course, the Marine player had the option to move his predator. The beauty of crushing one flank is that your opponent will have side armour shots in mind (the angles may not be so oblique), usually meaning he ends up twiddling his vehicles in an attempt to present the best facing.

What could he do? If he turns to face the prism on the left, the Eldar could have reversed the manoeuvre and shot it in the side with the other fire prism. Moving away from the wood would have likely resulted in the same thing. Reversing would work, but would play into the hands of the Eldar player since its role in the battle would be reduced (and suit the superior range of the prism cannon).

The imperial player has a major threat in his flank, but also has to deal with the bulk of the Eldar force coming from the other direction. The result is that both your opponent and his army are under pressure, which can result in mistakes that suit your strategy.

As a footnote, I don't intend to say that fire prisms should always work together. Sometimes two S9 (/S5) shots can be a better idea than the one big shot of doom. And remember those oblique angles can be achieved with falcons, vypers and even jetbike shuriken cannons. The fire prisms are something I use, and show how it can be important for mutual support between units.

PrOtOcoN
June 30th, 2007, 10:59
An excellent overview of how to use prisms Rork.
Made for an interesting read and the pictures were nice and explanatory :D

Now to foil this plan *plots* :shifty:

PaRaSiTe_X92
June 30th, 2007, 16:25
I said on IRC, but great tactica! You've actually made me want 2 Prisms now!

Rork
July 8th, 2007, 21:09
Part II - Synergy and 'plans never survive contact with the enemy'

In the world of gun lines and assault armies, the Eldar provides a counter-point to both - the mobile army.

With jetbikes as troops, the Eldar have the "Go anywhere, do anything" strategy as an effective strategy, much to the consternation of 'traditional' 40k players. Paying out 76pts for a 3 wound shuriken cannon gives you a nasty heavy weapon and a scoring units (in power armour!) for a throwaway price.

So once again we're talking angles, but also a bit about broader unit synergy. I've found over the years using both an infantry and bike army that having your army work as one bit unit is a good way to ensure success.

So lets introduce some bikes -



So that's a las/plas tactical squad, assault squad and two predators vs two prisms and a unit of bikes (the pale green triangle).

Now, as you can see, I've marked the arcs of the right-hand predator's armour. The problem the bikes have is that they're effectively pinned down by the predator, which can threaten them and the prisms on the left flank.

A further problem is that they have to move almost their entire move to get into the side arc, in turn bringing them deep into assault range of the assault marines.

So let's see what happen when the Eldar roll the dice.



Good old prisms. Using careful use of LoS they've nuked one predator, while remaining out of sight of that pesky tactical squad.

But those pesky bikes weren't so lucky. Their BS3 and S6 gun has resulted in them only shaking that predator, and needlessly exposing themselves to the assault marines. So what happens now? You're going to lose one scoring unit and let the marines get away with it.

Or are you?

Eldar jetbikes. Love 'em. The crafty buggers represent hit and run warfare at its best thanks to their 'free' assault move. But what happens when you've got nowhere to run?



To the dead ground! A killer use of LoS for any army is give the opponent nowhere to hide his expensive units. In this example the Eldar player can rely on the prisms to be active after the next marine turn - so you've got a nice AP3 blast if you need it.

This results in one of two things -

1. The assault marines take the bait and attack the bikes, wiping them out, but whatever distance they consolidate, they'll be left in the open to face the large blast of linked prisms.

2. The assault marines cower, the bikes then get away leaving the prisms to take out the 2nd predator (possibly with the bikes still helping!).

So we're looking at mutual support, even though the two elements of the Eldar army are more than 48" away from each other. So by keeping the prisms in mind when part of the plan goes wrong, you're still looking at controlling unfavourable situations if you use distance (of enemy charges) and LoS (of the prisms) to your advantage. One flank supports the other - one big unit.

PaRaSiTe_X92
July 8th, 2007, 22:15
Wahey, Rork, you wrote part II! Very nice, even more similar to my army list! Melikes! :yes:


To the dead ground!
I assume by that you mean the area that can be Prismed, yeah?

Rork
July 8th, 2007, 23:05
Wahey, Rork, you wrote part II! Very nice, even more similar to my army list! Melikes! :yes:


I assume by that you mean the area that can be Prismed, yeah?

Yes, basically the area that's open and has good lines of sight into it.

Manu_Forti
July 9th, 2007, 03:56
Not a bad tactica, but a few points I would raise:

2 prisms would probably only be fielded @ 1000pts minimum, usually higher. So there would be a lot more units (for both sides) than shown in the diagrams, which changes the whole scope of things.

In the second part, I would probably do things differently. The furthest-most Pred isnt much of a threat where it is yet, but the closest one is pinning your bikes. So, I would either:

A- leave the bikes there out of harms way for now (I definately wouldn't bother attacking a Pred with BS3 S6, bad move), & fire the Combined beam at the closest pred, destorying it easily against side-armour. Freeing up the bikes. Then send another combined beam at the rear Pred next turn, while the bikes can now freely harass the Assault marines.

Pretend the Space marine deployment table edge is North.. You could move the rear Prism West, almost right back into the corner.. then move the other Prism SE, behind the building. The result will achieve option A, and keep BOTH of them out of LoS of the Tac squad AND the other Pred. In your example, the rear Prism is exposed to East Pred, which will most likely atleast shake it (Twin linked Lascannon :ninja:). Which leads me to my next point below.

B- Move the Prisms as shown, but fire 2 S9 beams, 1 at each pred. The rear Prism has a clear side-armour shot, so a S9 should do the job, as long as it hits (66% chance)

Probably option A.

Hiding them both behind cover and then popping out as shown, is definately the way to go. But never count on getting 2 combined shots in a row. They may be hard to destroy, but not hard to shake.. you can almost count on 1 of them being shaken (atleast) after revealing themselves for the first combined beam.
Then youve got 1 non-combined shot, while the other ducks back behind cover to recover. Its best to plan around this scenario, not 2 combined shots in a row. IMO of course..

Cheers :)

Rork
July 9th, 2007, 14:13
Not a bad tactica, but a few points I would raise:

2 prisms would probably only be fielded @ 1000pts minimum, usually higher. So there would be a lot more units (for both sides) than shown in the diagrams, which changes the whole scope of things.


What I'm demonstrating here is an abstract of how it works. In part I, I'm still assuming there would be other elements on the table, but to keep things simple I'm only dealing with the units that pose a serious threat.



In the second part, I would probably do things differently. The furthest-most Pred isnt much of a threat where it is yet, but the closest one is pinning your bikes.

Hiding them both behind cover and then popping out as shown, is definately the way to go. But never count on getting 2 combined shots in a row. They may be hard to destroy, but not hard to shake.. you can almost count on 1 of them being shaken (atleast) after revealing themselves for the first combined beam.

Then youve got 1 non-combined shot, while the other ducks back behind cover to recover. Its best to plan around this scenario, not 2 combined shots in a row. IMO of course..
I'm not saying my way is necessarily the right way - I'll gamble if the opportunity presents itself. I would probably try for the side armour since 3 bikes with a shuriken cannon are fairly expendable. Part II would be a flanking strategy down the left - if the assault marines do attack, it wouldn't really be a disaster - the prisms would probably be better off taking down the las/plas squad to roll that flank. But it is useful to make your opponent over-analyse and use that to trip him up.

Certainly I've had linked shots miss, and prism cannons being blown off in turn 2 or earlier. I may yet try to involve an example using my entire army, but that requires my memory to work {goofy}. I'm dealing with fairly general situations since not everyone uses the army I have. Mainly I'm trying to emphasise that you can use LoS to your own advantage in certain ways while using it against your opponent at the same time.

stjohn70
July 16th, 2007, 03:10
Rork,

I think you've got a great thing here, in discussing how to use the twin-firing capabilities of the Fire Prism.

That said, I think that more discussion on when said capabilities should and should not be used is in order. In many, many instances it is more desireable to have multiple target mitigation, rather than using two tanks to take down one target - unless said target is either extremely juicy and/or vulnerable.

Your part II is a classic example of using one shot, where you should be using two, IMO.

Were I to strategize the attacks, I would bring the left Prism behind the terrain to its right (thus protecting it from shots from in front of it - the tactical squad and the pred). It has a wide open shot on the far right pred's side armor.
The lower Prism would move right behind the first Prism (to essentially the same spot you have it on your diag). If you look, you will see that it is on the side arc of the top pred - even though it is obscured, I think that is the preferential shot.
The bikes would move to the same location and fire last. To ensure the Pred's destruction if the Prism misses, or to put shots into the Assault squad.

Again, I know this is just an abstract, but I think that there is a definate danger in looking to use the linked-shot, as you may well pass up better opportunites for target mitigation.
The Linked-Shot should be kept in mind as an option, but I really don't see it being a first-choice.

Sniperfish
July 26th, 2007, 17:36
2 Prisms vs AV13 odds of killing, correct me if I get this wrong :)

Unlinked: [Hit (1/2) x ((Glance (1/6) x Kill (1/6)) + Penetrate (1/3) x Kill (1/2))] x2
= 7/36
0.19


Linked: Hit (3/4) x ((Glance (1/6) x Kill (1/6)) + Penetrate (1/2) x Kill (1/2))
= 5/24
0.21


So the issue I would then take with this tactica is that it relies far too much on odds being in favor of the Eldar where in reality exposing the Prisms like that to score a minor hit on the Pred could well see a barrage of fire coming right back at it!

Otherwise, in relation to ones awareness of spacing and the ability to move and combine shots whilst choosing your targets and denying the enemy his it's a fine tactica.

Rork
July 26th, 2007, 18:09
2 Prisms vs AV13 odds of killing, correct me if I get this wrong :)

Unlinked: [Hit (1/2) x ((Glance (1/6) x Kill (1/6)) + Penetrate (1/3) x Kill (1/2))] x2
= 7/36
0.19


Linked: Hit (3/4) x ((Glance (1/6) x Kill (1/6)) + Penetrate (1/2) x Kill (1/2))
= 5/24
0.21


Well, you seem to have listed them as BS3, when they're BS4 (2/3 chance to hit).

So it actually works out as -

1 prism - 2/3 x 1/6 x 1/6 + 2/3 x 1/3 x 1/2 = 0.13

Two penetrating hits is not just multiply by 2, otherwise you could have a probability greater than 1 :O. It's x 0.13 again (i.e. doing the same thing twice), so 0.017.

Linked prisms - 2/3 x 1/2 x 1/2 (Assuming it hits first time) = 0.17

So against AV13 a linked shot is about a third (0.04 of 0.13) more likely to destroy the vehicle than the single shot. It's just a matter of deciding which type of shot is best for the overall plan (side armour 11 would be better for single shots).




So the issue I would then take with this tactica is that it relies far too much on odds being in favor of the Eldar where in reality exposing the Prisms like that to score a minor hit on the Pred could well see a barrage of fire coming right back at it!


It's not perfect, but it's trying to demonstrate the things you're trying to look for. In a lot of games you will always be exposed to fire, in which case it will be about minimising the amount of incoming fire, not eliminating it.

Sniperfish
July 26th, 2007, 20:44
Two penetrating hits is not just multiply by 2, otherwise you could have a probability greater than 1 :O. It's x 0.13 again (i.e. doing the same thing twice), so 0.017.

Only one would need the kill ;)

Thanks for spotting the BS3 mistake, I've got so used to BS3 guardians that I forget the Prism is different!

Still agree with you in principal :yes:


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