Basic plan

Here's the simplest plan for setting up. It gives you no Marines but you'll still have plenty of fun.

The basic plan

Here's the plan I suggest you start with, to keep things simple and to get you used to the way things work before you move onto the business of arranging Marine support. I recommend using Heroic or lower. Normal may be the best choice, especially for battling in which you don't allow yourself a sniper rifle, but it obviously depends a lot on your skill level and the enemy force you eventually fight. The more Elites and Hunters you face, the more reason you'd have to favour using Normal rather than Heroic. The pressure of high enemy numbers could easily make Heroic too hard to survive.

Nice collection ready, so let's go!

Develop a spiral path megabattle situation

Start by developing a spiral path megabattle situation, something I'll assume you're familiar with. Here are a few special points to observe in doing this.

Let all the early Marines get killed. By the time you reach the underground bridge, you'll probably want to be carrying a sniper rifle for potential use in the later battle. Also be fully stocked with grenades.

Before you trigger enemies in the spiral path area by flying through the pass low down, fly through the pass high up and go to the twin bridges area. There are Shades, Ghosts and a Banshee there, and you probably don't want any of these to get manned later. You can prevent that by blasting them over, maybe positioning some as rocket targets or extra cover. In regard to the Banshee, you could instead steal it and make sure to be in it when the pilot materializes later (or have it overturned somewhere), so he remains helpless on the ground.

Drawing enemies out of the pass

Sometime before triggering the Marines and Hunters, it'll be handy to get armed with an AR for forthcoming use in tempting enemies through the underpass. But you could leave that for later if you prefer.

When you've triggered enemies to move through to the spiral path area, try to draw enemies out of the pass (i.e. properly into the spiral path area), as this should ensure that they later come down the path and into the twin bridges area. It won't matter much if Hunters remain in the pass, because they can easily be led out later. Other enemies can be harder to shift though.

When you trigger the Marines and Hunters, kill the Marines. The neatest way is to skim across the ice and scythe them down in one go as they come around the ice path in a neat line. But be careful not to fly straight into a Hunter blast! Leave the two Hunters alive if you want to get them into the eventual battle (you can end up with four).

To be honest chum,that sword's a bit of a giveaway

Trigger the underpass guard and others

Fly over the underpass and land near its exit. Dismount and go in far enough to trigger a cloaked Elite guard (or two on Legendary). Reaching the final rock shortly before the entrance pipes will suffice; but if you got low past the underpass checkpoint trigger line earlier (entering the trigger zone for that checkpoint), it suffices merely to go about a metre inside. Kill the guard and reboard your Banshee; or just run past then kill him with the Banshee.

Why did I say to land near the exit rather than the entrance? That was mainly to keep you clear of the nearby Hunters if you left them alive, but it will also keep you clear of any pursuing enemies.

When you triggered the guard, you also triggered a Shade gunner on the roof and an enemy squad in the next area (an Elite and four Grunts, on Heroic). Kill the Shade gunner, either now or shortly.

Low over the zigzag path

Trigger more enemies

Fly low over the zigzag path that leads up into the twin bridges area. This triggers a second bunch of Grunts, one of whom was hoping to man a Shade. You'll also be due a checkpoint, though it'll be delayed until you're free of threat.

Continue on past the big tree straight ahead, still quite low down (about half tree-height). Additional enemies are triggered and the music will stop shortly. Pause to let a newly triggered Elite leave the trough, then fly down into it to trigger two Elites lurking in the side passages. Preferably avoid triggering the two door Elites yet; stay well clear of the door.

Obviously you should feel free to eliminate any enemies you're not interested in. Maybe you only want free-roaming enemies for example.

Yay! Another two party guests

Tempt old enemies through the underpass

Flying low over the zigzag path will have altered the behaviour of enemies in the spiral path area. There's now a general desire to head for the underpass and potentially through to the twin bridges area, as opposed to just chasing after you. Except, enemies that were still in the pass when you triggered this new behaviour are likely to be a bit obstinate about moving, Hunters excepted, which is why I emphasized drawing them out of the pass beforehand.

Head back and hover in the vicinity of the zigzag path, high enough to be out of danger. A few enemies (probably Elites) may come straight through the underpass and into the twin bridges area; but even if so, the trickle probably won't last long. When it looks safe, land near the underpass exit and tempt enemies through, an operation I've detailed separately. Make sure the Banshee is well off to the side, else enemies may get caught up by its legs.

So many lovely choices…

Maybe arrange some spare weapons

Now you've got the twin bridges area teeming with battle fodder, preferably take a moment to assemble a handy stash of spare weapons near the underpass so that each time you're about to head into battle, you'll have the option of switching your combo. There are already four different weapons by the underpass entrance, including a plasma rifle on 100%. You can get a plasma pistol on 100% from the gunner on the roof, and you could've brought a sniper rifle and full needler with you from earlier in the level. If you didn't bring a full needler, potential sources were the Banshee pilot in the tower area, and enemies that passed you as you tempted them through the underpass.

Get ready for battle

Use a medkit if necessary, check that you're loaded with grenades, and get armed with your preferred combo (you'll still be able to switch before each battle though, using any spares available). Maybe switch to a fresh Banshee.

Checkpoint… done

Get a battle start checkpoint

If you haven't triggered the door Elites yet, you can finish off as follows. Fly low near the door to trigger them. Going close past the stationary shields is near enough. The 'door checkpoint' is now due but it'll be delayed while the game considers you under threat (and you can always keep things delayed with Banshee fire if you need to). You can kill the door Elites if you want. Get the checkpoint by getting more distant from the enemy. For a general purpose save I have two suggestions. One is to fly back to hover over the underpass, then slowly back off until you get the checkpoint. Alternatively you could get the checkpoint at your stash of spare weapons, so you can swap weaponry quicker when desired.

If you've already triggered the door Elites however (accidentally or by choice), or you prefer to do things this way anyway, fly off to trigger a tunnel checkpoint, and keep it delayed with Banshee fire until in your desired starting position.

Tempting enemies through the underpass

At the underpass, enemies tend to get stalled by the narrow section and you have to tempt them through. The trick is to get them shifted so they have a relatively clear line to the exit. This seems to free them up to advance into the twin bridges area. I've got lots of tips for you here. Preferably have an assault rifle for this. If you don't already have one you can get one back near the huge tower in the earlier area. However, a pistol or plasma weapon can also be used.

Get a move on won't you?

Shield shooting

To begin with you tend to have a lot of Elites and Jackals to the fore. Shooting their shields will cause them to dodge or roll, hopefully freeing them up to advance. When you see an enemy coming through, retreat behind the tree while they pass. Sometimes there's a cascade effect and a succession of enemies will trail through in a line. It's usually just a few, but I've seen a mass exodus of around 20 a couple of times, which is like hitting the jackpot! When the coast is clear, come back out for more tempting.

Closer work

If you can't seem to tempt anyone else through like that, it's time for some other techniques. One is to make an Elite swipe at you, to move him into a position from which he'll then come on through, or at least be closer to doing so. Meanwhile you dodge and get clear. You might take damage but there are four medkits available; three nearby and one back in the tower area. It can be worth taking a plasma pistol however, especially if you're going to be exposed to other enemies. If you misjudge things and find yourself suddenly in danger of being killed by an aggressive eight-footer, you can quickly stun him with a plasma ball, giving you a few seconds to get clear.

That's it grunty, clear off

Another technique is to repeatedly fire off shots from close behind a rock to make Grunts jump in surprise, which tends to move them to their right a bit. They have such a short memory that you can make them jump every few seconds, which gets quite comical. Gradually they shift along until finally deciding to toddle on through, at which point you can either retreat and hide or, if they're panicking, just stay put and let them harmlessly run past. You'll probably need this technique a lot towards the end of the process, when you tend to be mostly left with Grunts.

Obstinate enemies

There are some cruder techniques you might use on obstinate enemies. You could shoot a Grunt with a feeble AR round or something, hoping to make him hop to one side. You could weaken an Elite until he enters rage mode and comes after you. As long as you hide quick, he'll lose interest and continue on. You could even resort to killing an enemy, sacrificing him in the hope of freeing things up inside for other enemies to move forward. But there's rarely any need for these damaging techniques if you're prepared to be patient.

Minimizing friendly fire

During this whole process, enemies can get killed by friendly fire. Try to minimize this by not exposing yourself to too many enemies at once. Also, if an Elite has lost his shielding, perhaps due to taking a Jackal blast in the back, you might like to give him time to recharge.

Move along Mister

Occasionally you may get an enemy who's out of the underpass but just standing around, perhaps wondering where the heck that cyborg went. A few shots into the air should get him moving on. Sometimes you might even get an enemy heading back into the underpass; but shots into the air should quickly turn him around.

Ok spiky, follow me!

Hunters

Hunters are usually the last guys left and are often some way back from the underpass. You'll need to lead them along and through. That's a fairly routine job if there are only one or two around, but with more it can get a bit dicey trying to extract one without getting blown sky-high by the others. It could be worth getting a delayed tunnel checkpoint prior to attempting such risky work. Once you get a Hunter through, dodge a final swipe and hide. He'll quickly forget about you and clank his way up into the battlefield.

How long does it take?

So, how long does all this take? Except for Hunters, I find that I can get enemies through at around 2 per minute on average, so I'm usually done within half an hour. If you're not so fussy about getting every last enemy through in good health, you could be done faster of course. But I'd recommend taking the extra time to do a good job as you'll probably be playing your eventual save a lot. It's worth investing the time.

Killing the door Elites

Close-range surprise

If you want to kill the door Elites prior to getting a battle start checkpoint, there are various options. The easiest is to pause your Banshee close to the door - perhaps off to one side is best - and blast them as they emerge. Another quick method is to directly face the door very close and squash them as they move forward to run out. That's great when it works like that, but sometimes one of the Elites is standing well back and you have to resort to opening fire. With both of these methods there's a significant chance of taking Banshee damage, but if you don't mind losing a bar or two, or if you plan to switch Banshees before getting your battle start checkpoint (maybe you intend to use a delayed tunnel checkpoint rather than the door checkpoint), that won't be much of a concern.

High bombardment

If you want to be more protective of your Banshee's health however, climb to around the height of the first ledge to be reasonably safe from any enemy fire, then blast the Elites with carefully aimed shots. It takes a while and sometimes they hide behind trees which can make it fiddly, but it seems reliable and you take no Banshee damage at all. The game tends to consider you under threat when you're still this low down, and accordingly the door checkpoint should remain delayed. But if you want to make extra sure it stays delayed, just keep up a stream of fire (see general advice on checkpoint delaying). The enemy mass will close in on your position while you're working on this, so afterwards you'll probably want to give them time to return to the start of the battlefield.

Advantage of elimination

I usually do eliminate the door Elites. If you leave them alive they can be an annoyance when you want to defend on that side of the battlefield (my favourite side). With a massive horde charging your way, you don't really want to be distracted with fire from your side or rear. Still, it's up to you.

A few extra enemies

When using the basic plan there are a few extra enemies you can get into the battle (rather than just killing them) if you're willing to put in the additional effort needed.

Out of that Shade!

Getting the spiral path Shade gunners

There were two Shade gunners in the spiral path area, on the ledge above the ice path. If you push a manned Shade off the edge with your Banshee, the gunner will potentially get ejected intact and be able to move through to the twin bridges area along with everyone else, making an extra unit of battle fodder. Yay! When pushing a Shade off, I suggest you push violently rather than just nudging it off. I think the gunner tends to stay seated longer, which increases his chance of surviving when eventually unseated (if at all). It's best to attempt each ejection just after a checkpoint because it's likely to take multiple attempts to get the gunner down alive. You can use a delayed tunnel checkpoint for this.

You're likely to take Banshee damage when doing this ejection business, but you can potentially switch to a fresh Banshee later so it shouldn't matter much. All the same, try to be swift and decisive.

Happy landings grunty

Getting the underpass Shade gunner

There's also a Shade on the underpass roof, whose gunner spawns with the cloaked underpass guard (or guards). Originally I thought he wasn't able to take part in the battle, due to what seemed like an inability to move into the battlefield once I'd got him down to the ground. But I guess I should've tested more thoroughly, because I've since found that he can take part, just like the spiral path gunners. Also, getting him down is a lot easier than I originally thought. Here's my advice.

You can't just push the Shade off the edge, because there's a rim around the roof which stops it (and the idea of moving the Shade off the roof before the Grunt spawns is no good, because he won't man it). Instead you should blast the Shade so the gunner is ejected over the rim to then bounce off the sloping ledge wall (below where the ledge ends), ideally near the ground. The bounce sends him skimming along the sloping ground, and the net effect is that he gets cushioned enough to survive. The ejection is easily done with a Banshee blast or grenade, but it's worth getting a checkpoint beforehand in case it doesn't work first time.

Uh-oh, he's come back to get me

Getting underpass guards

In the plan I said to kill the cloaked Elite guard (or guards) at the underpass. Actually though, if you instead just bypass him he'll potentially chase you into the twin bridges area and be able to take part in the battle later. That's nice, but there's a danger. Even after you've drawn him into the battlefield, he may get attracted back by the sound of your gunfire when you're tempting enemies through the underpass. Therefore you need to stay alert to make sure you don't get sliced up by surprise. I think it helps if you do your firing relatively close to the underpass exit. The closer you are to the zigzag path, the more likely it is that a guard will be attracted back.

If a guard does come back, you have two options. One is to hop into your Banshee quick and try to draw him into the battlefield afresh before returning. It'll probably help to get him growling, but you may find him reluctant to move. On at least one occasion he was too obstinate about moving, so I had to give up and kill him. The other option, and perhaps the better one if you don't mind the danger, is to try and hide from him using the rock, tree and Banshee. When he's lost track of you he should return to the battlefield.

Note: This same potential danger and fix may also apply to any cloaked Elite you brought along from the tower (I need to check that sometime).

Rocket targets and extra cover

Let's try a few here

If you leave an object somewhere in the battlefield where the enemy may later be passing, you can enjoy rocketing it to send both it and nearby enemies flying, or to send the object skittling along towards enemies. It's something I've previously enjoyed a lot of in the spiral path megabattle. Ghosts and Shades are best, being lightest. Sometimes enemies may even move to such objects for cover. Not a good idea folks. BLAM! Think about good places to put such 'rocket targets'.

You can potentially also use objects for cover of course, perhaps as you back off from an enemy charge, or perhaps forming a specific defence position from which to try and hold off the attack.

Note: If you're using one of the two Ghosts already in the battlefield, you'll probably want to overturn it else the pilot will run to it when he spawns later, and drive it off. However, if you're confident of being able to kill him before he gets there, you could leave it upright.

Manned Ghosts

And that takes care of him!

In the plan, I suggested that you overturn the two Ghosts in the twin bridges area in advance so they don't get manned. But if you like the idea of having to tackle Ghosts in the battle, you could leave them upright to get manned after all.

However, bear in mind that while they're hovering around prior to you getting your battle start checkpoint, they may run over some enemies or get overturned, or get attracted your way when you're tempting enemies through the underpass. So, it's problematic and may take a few attempts. But I have managed to set things up ok with manned Ghosts, so by all means give it a try if you're keen. You'll probably want a rocket launcher for the battle though!

One-shot piloting opportunity

Incidentally, it seems that once a pilot has noticed that his Ghost is overturned, he won't get into it even if you subsequently right it (which is different from pilot behaviour earlier in the level). That puts paid to the idea of leaving them overturned and righting them later to get them manned. A similar thing appears to go for the Banshee pilot and Shade gunners.