So, yeah, tank shock, I rarely do it. More often than not I forget about it. When I do manage to remember and decide to tank shock I never seem to get much benefit from it. I think the most damage I have caused is mowing down a Trygon with a Battlewagon!
What am I missing with tank shock?
Tanking the knowledge
Basically when doing a tank shock you are using the vehicle's mass as a weapon, a sort of battering ram. In order to tank shock you just point the tank in the direction you want to go and declare how far it is going to move. Depending on distances you could tank shock multiple enemy units.
When an enemy unit is reached it must take a morale test, if it fails, then the unit will fall back. If the test is passed then the enemy unit will let the tank straight through.
If any enemy models are 'under' the tank when it reaches it's final position then they must move 1" out the way. If the models cannot move 1" out the way then they are crushed and removed as casualties! The beauty of this is you can trap enemy units against the board edge, impassable terrain or even 'sandwich' between your own units and box them in - if there's no place for the enemy models to be placed then they are mushed.
Units which have failed morale tests and are falling back auto fail tank shock tests; this allows you to keep pushing units back towards the edge of the table - gives like a free fall back move in your favour.
If tank shocking enemy infantry isn't good enough then you can use the tank to ram other vehicles - this is particularly useful if you have a basic transport vehicle doing nothing or a useless weaponless vehicle i.e a Vindicator. A tank gets +1 for each armour over 10, +1 for being a tank, +1 for each 3" speed it has moved. A Vindicator moving 12" would dish out a nasty S8 hit - great on the side armour. Of course your own tank takes damage the same way.
It is not all guts and glory for tanks, the enemy unit can have some of the limelight too and that is by deciding to do death or glory. A model in the tank's path can decide to stand their ground and do some damage against the tank, this is a single attack and auto hits. The enemy model needs to cause crew stunned, immobilised, explodes or just wreck the tank in order to stop it. If not, then that model is brown bread. The key words here are model in the tank's path, so if you tank shock a unit and that meltagun is over the other side of the unit and no where near the tank, then it means that meltagun cannot attempt death or glory.
Tanking the shock
Tank shocks are effective for making enemy units fall back, even better if those units are falling back already i.e in your previous turn enemy unit failed morale and ran, they failed to regroup, tank shock them again and they auto fail. This is an excellent way to escort enemy units off the board or at least away from the action. Doing this gives great control over the opponent's units and dictates the flow of the battle.
If you position your own units prior to tank shock, then you can box enemy units in and drop the tank on them. Enemy units have to move 1" away from the tank, if not they are crushed and mushed. This is a super way of taking out units just by using simple movements and a little thought.
Tank shocking is handy for forcing units off an objective, just ram that tank up there and watch the units run away like big girls. This is even better if you have a unit inside your vehicle as they can get out next turn and you can use the vehicle to shield your unit from enemy fire and use the tank as a blocker between the objective and enemy units - remember enemy units cannot come within 1" of an enemy model and a Rhino is about 3" wide.
Tank shock also stacks nicely with shooting; if a unit has failed a morale test from tank shock, then blast that enemy unit and cause 25% damage - if a unit if falling back then it auto fails morale tests and continues to fall back, that's two fall back moves in a single turn - an average of about 14" fall back.
Shocking fail
I think the reason I do not tank shock is that a lot of units in 40k have pretty high leaderships. I think the lowest is LD7 and the average 2D6 roll is a 7. Of course you do not rely on a single tank shock and use multiple tanks to get the job done, you just move one tank at a time. The more leadership tests a unit has to take then the more chances of failure.
Tank shock, do you do it or isn't it with the bother?