Editing Warhammer 40,000/7th Edition Tactics (section)

===Shooting Stuff===

====The basics====
*Choose a weapon to shoot with and throw a dice. To hit, you need to score higher than your BS (which may vary due to external modifiers like cover).
* Rolling to wound:

**Attacker's Strength two (or more) greater than target's toughness: 2+
**Attacker's Strength one greater than target's toughness: 3+
**Attacker's Strength equal to target's toughness : 4+
**Attacker's Strength one less than target's toughness: 5+
**Attacker's Strength two (or more) lower than target's toughness: 6+

If the target's toughness is double (or greater) the attacker's strength, then the target is completely immune, the attacker can't damage him. Conversely, if the attacker's strength is double (or greater) the target's toughness, the wounds gain the rule "Instant Death" (meaning any unsaved wounds insta-kill the target).
* There are two ways to kill a tough unit: Either you use a high penetration high damage weapon to greatly reduce the chance of the unit succeeding its armour save , or you can attempt to overwhelm the unit's defense and fire enough dakka into it to make it fail a save. Bring the appropriate amount of dakka to combat a heavy unit, lest you be the one shot to hell.
**Example: Space Marine Terminators '''hate''' Guardsmen, Necron, and Tau bricks because they put out a fuckton of weak shots that will make them inevitably fail armor saves. Or rather than rely on 50 lasgun shots the guardsmen can instead bring a plasma gun that can flush their armor saves and instantly kill them. The plasma gun only needs to cook one terminator to make its points back. Conversely, the terminators can bring a heavy flamer and viet-nam 80% of the guard squad.
*Consequently, using too many units on a weak enemy is a waste of firepower and resources. Every unit who is somewhere can't be somewhere else.
*Although over-kill might be considered bad by some, lady luck might not always be on your side. You want to succeed even if plans A, B and C fail.
*During your shooting phase, assess what target options each one of your shooty units has, and always have your units who only have a single option fire first. The reason for this is if you've got unit A in a position to shoot anything he likes and unit B which only has one thing to shoot at, you want B to take the shot first. If you shoot B's target with A first instead, you run the risk of destroying it or breaking their morale, and you'll feel like a complete moron for depriving B of anything to shoot at.
*Another thing that is good to remember is which guns to fire first. Always fire blast weapons first, because the number of wounds they deal is always equal to the number of units in the squad at best, whereas regular guns can deal as many wounds as they hit.

====Advanced Notes====
* Generally speaking, don't rely on blast or flamer weapons to rack up large numbers of kills, as an enemy general can easily spread out his models to minimize potential damage. More than anything, they exist to keep the enemy honest and prevent an extreme concentration of forces. That said, there are four major scenarios for enemy models to bunch-up.
**When the enemy is displaced from one or more Tank Shocks.
**When a unit emerges from Deep Strike, and either rolls poorly to Run, forfeits running to-shoot (though a lot of Deepstrike units can reliably "Fire & Run" with the right power combinations), or is targeted by an Interceptor Weapon beforehand.
**When the unit rolls poorly to consolidate after an assault (of note is the fact that models cannot consolidate after assaulting a vehicle). Don't forget your flamers for the second wave.
**When the unit loses its transport, either to a wreck or explosion. A classic "one-two-punch" for a Marine army is to use heavier weapons to destroy enemy transports, then immediately follow-up with the Thunderfire cannons before the surviving passengers can spread out!

* If you want to maximize the amount of damage done to bunched-up models, four AOE weapons firing from the same unit will inflict more damage, than from four different units. To use a (very vacuum) example, let us compare two (vacuum) scenarios, with Orks as target practice:
**Four units of Chaos Space Marines, each with one flamer and 4 Bolters, fire at a unit of 20 Orks. All other things being considered, each flamer-equipped model can hit roughly 5 Orks apiece. The first unit fires, with one flamer hitting 5 Orks. After rolling to-hit and wound, the flamer kills about 2-3 Orks. The remaining models fire their Bolters, and probably kill another 4 Orks. The next unit fires, and is lucky if there is even one Ork in range of its flamer.
**On the other hand, let us suppose a unit of Chaos Chosen with four Flamers was firing at the unit of Orks. Each one hits 5 Orks, for a total of 20 hits. You now roll to-wound and the flamers themselves kill an average of 10 Orks, for a fraction of the investment.

*Many squads gain a disproportionate amount of strength from any special/heavy weapons they are carrying with them, or from the occasional superior character leading said unit. As a result, there are some occasions where you can mostly neuter the strength of the unit if you kill those specific models. 

* Although Characters can get "Look Out Sir" rolls, troopers armed with upgraded weapons do not. Thus, a competent player will generally hide such models in the "Center" of a formation, where they are shielded by their buddies (since the closest models from an attack vector are hit first).

* There are two main ways to single out enemy models in a unit: The first is to use weapons which can single out specific models. This includes attacks with the Precision Shot rule, or Beams/Focused Witchfires. These attacks tend to have inefficient economy of force. 

* The second way is to force key models to be the the closest visible ones singled out by your firepower. This is generally more efficient, but is situational and requires more prep-work to pull-off. Several ways to more reliably force your attacks to wound the models you want dead include the following:
**Using "Barrage" weapons (Mortars/etc) changes the attack point of origin from the firing unit's location, to ground-zero of the blasts in question.
**Though it's basic, it bears repeating: Always keep careful track of the order in which the models in your unit fire. A good motto is "Area of Effect Weapons First", "Rank and File Weapons Next", "Specials Are Last But Not Least." You want to remove as many chaff models as possible before you give your Plasmagunner a clear shot to the enemy Plasmagunner. 
**If you have ready access to powers that let you move and fire during the Shooting Phase (Battle Focus, Feints & Ambushes, the "Fire & Move" order for Guard, Marines in a Stormlance Demi-Company, etc), you can line troops down one attack vector. Units that can move after firing can move aside so they don't grant the enemy cover from your next firing squad (think of center-peeling and you're not too far off). Units that can move-then-fire in the shooting phase, you can further reposition your models based on any opportunities to hit the "next closest model".
**If all else fails, you can aim to block visibility to the parts of the enemy unit you don't want to shoot. This is yet another reason why Rhinos and convoy formations can be nasty. You can play "Space Invaders/shooting gallery" with your troops forming a triangle, and firing at a distinct subset of models they wish to remove.