Against armies with massive firepower, there is one easy way to keep your key units from being shot up. Ensure they are in hand to hand on the opponents turn. Simply put, if you are locked in hand to hand, the opponent can not fire on you. This can be used effectively against especially against some of the current top tier armies including Mech MEQ and Guard. Ask any guard player and they can tell you it’s not going to plan if the opponent has units in hand to hand on a guard turn.
It’s important to note that multiple assault actually begins with the move preceeding the assault phase. During your move to set up a multiple assault you must be careful to stage your models so that when they do assault they will be able to bring in two units into combat. Usually if there is 4” of room between units, you can make a multiple assault work if you move your models into the gap between them. If done correctly your own models will build a bridge for coherency allowing you to tie in units that are up to 4” apart. (If your assaulting models have bigger bases like bikes, thunder wolf cavalry, or fiends you can bridge even farther)
Remember when you do assault, you must move the closest model to closest model via the shortest route against the declared assaulted unit. After this, each model in your unit must move to be in base to base with a different target if possible. Beyond this, you may freely bring in other units providing you do not break coherency. This works especially well, if your first target is a vehicle or tank and there is another squad nearby that you can also assault.
If you are angling to stay involved in a combat in the opponents round your goal should certainly be to bring in a second unit into combat. Ideally, you want to bring in a second squishy squad but direct the minimum possible attacks at them. You want to beat on the more resistant squad, or the squad that has the potential to damage you the most. Fearless targets can also make pretty good secondary assaulted units providing they won’t tie you up for more than an extra turn. You want to end the fight and stay engaged with the second unit.
Against daemons or Tyranids, think about assaulting a unit of fearless troops and a monstrous creature at the same time. Swing attacks against whichever target will provide you with a stick into their turn, but leave you with one unit you will most likely kill in their round of hand to hand. Don’t forget that their units will take additional saves because they are fearless – don’t kill everything you are fighting off on your turn! (Killing monstrous creatures through a multitude of fearless saves, by beating their bubble wrap to death in a multi charge is another ‘trick’ everyone needs to know).
Against Guard, Eldar, Tau or Dark Eldar, assault a vehicle and a squad at the same time. Swing attacks against the vehicle and leave the squad for next turn. OR If all troops are in vehicles, open one up with a melta or ranged attacks and then assault its innards while bringing another enemy tank or vehicle into the assault. Swing your assault attacks at the new tank leaving you with the squishy troops to deal with on their turn.
Against Marines, Assault and wipe out a primary unit and choose either a tank or another squad for the secondary target. Be careful on what you assault – you want to stay locked. Hopefully the marine makes their leadership check, or you beat them on initiative and they become fearless. You don’t want them sneaking away via combat tactics.
So what units excel at multiple charges or what unit needs the multicharge to do their job effectively? Deep Striking Vanguard – they need to stick around beyond their initial heroic intervention, and to do that you need to multi assault so they aren’t shot up immediately.
Fiends and Harlequins and things with Hit and Run are great at multi assaults. They are also usually too fragile to weather shooting after their first assault. If your units have hit and run you don’t have to worry about being tied up indefinitely if the chosen target manages to stick around longer than they should.
Fast moving units like assault troops or beasts are also great at bringing in more than one enemy unit. Their extra move or assault give plenty of room to work with to maneuver to grab that extra foe. Gene Stealers are another perfect example of a unit that performs much better if it can’t be shot at!
Well then, what's the catch here? Sometimes staying locked is easier said than done. The dice will turn on you eventually and the enemy will turn tail and run – leaving you high and dry. Staying locked in combat is never a sure thing. If the unit that was supposed to keep you in combat breaks, hopefully you are in the same position you would have been in if you hadn’t gone for a multi assault lock…. Your unit simply gets shot off the table but you have maybe wiped out two units instead of just the one.
But worse than being shot off the table, is if the enemy actually sticks for longer than they should have effectively tying you up on your next turn. This can spell doom to a unit that needs to be killing each and every turn, such as an eldar seer council. Now you have been mobbed and the plan has backfired and you are giving your opponent time to respond and maybe even ignore your deadliest combat units. You must realize on that second round of combat, in your opponents turn, you are swinging with less attacks. You have to have enough attacks to finish the job or your in trouble.
Planning out a multi assault involves a lot of gauging of the enemy strengths, but if you become good at it, it will flat out win you games. Even if you don’t use the multi assault often, you need to understand it so you can counter it when you are facing an assault army. Assault armies need the assault chaining to dominate the game. If you can stop it from happening, you are putting yourself in a much better position to win.