Extra Marines in the grav-lift battle
Posted January 21st 2007, reworked May 17th 2026.
Associated movies
When you enter the grav-lift area, your existing Marines initially hang back in the approach passage, giving you a chance to do some cloaked stealthy killing if desired. But if you get sufficiently far into the area (e.g. nearing the trees up on the right) and the Marines still haven't been triggered into action by the covies getting alerted, something interesting happens. Cortana calls for reinforcements, presumably because you're now deep into enemy territory without support. I suspect this is actually a slight flaw in the game logic, as if the programming has neglected to consider that you might still have Marines waiting just outside. But regardless, it's a welcome gift!
The incoming Pelican brings five fresh Marines, including as a bonus either Stacker or Johnson, randomly chosen. Needless to say, these extras should be quite a help in the coming fight, so this little trick is well worth doing. With the aid also of some careful earlier work, you can potentially then tackle the battle with ten healthy Marines! Elaboration follows.
Working the trick, in more detail
At the start of the approach passage, a checkpoint is triggered and there are some Elites and Grunts who'll come out after you. Try not to let any Marines get hurt when dealing with these guards, as you'll want them healthy for the battle beyond. Sometimes a guard may obstinately fail to emerge, in which case you can leave him for later when you're cloaked.
After this, you can make any preparations needed for the forthcoming battle. Backtrack to a medkit if needed, top up with grenades, and get armed with your preferred weapon combo.
Now get cloaked with the active camouflage. As you head through the passage, a checkpoint is triggered where a ground light projects brightly up onto the left passage wall. That's worth getting and saving as a battle start checkpoint, if you're interested in repeatedly fighting the battle. In this case you could even have placed alternative weapons nearby, to potentially choose from each time. A deluxe set-up, as it were.
You may need to pause a moment to get the checkpoint, by the way. And of course, it's important that you didn't trigger it earlier when dealing with the passage guards (you'll notice in my tutorial movie BCM633 that I kept back).
All you need to do to get the reinforcements is get far enough into the grav-lift area without your Marines having raised the battle cry ("Contact! Enemy in sight!" or suchlike), something they'd only do if the covies have become sufficiently alerted. It looks to me like there's simply a certain straight line you need to reach, stretching across the area (it's easy to check for points at which Cortana will make her request).
On your way though, feel free to do some stealthy killing, which could include some grenading or even sniping. You should have time and it'll ease the later entry of the waiting Marines. Alternatively though, you could leave such killing until after triggering the reinforcements. It can be fun to snipe them from distance for example.
When the waiting Marines finally give the battle cry, they'll usually advance. There can sometimes be a hold-up though, which I think may to some extent depend on how far away you've got from them. You may need to move nearer, to get them advancing.
Getting ten healthy Marines
To get maximum support in the battle, you'll want to be approaching the grav-lift area with five healthy Marines. One way to do this is to keep your original guys pretty much out of the action as you fight through from the start. But on the higher difficulty levels that's rather hard, especially if you want to retain all your sniper ammo for the grav-lift battle.
The easier way is to let your guys get killed off, so you end up getting reinforcements in the dustbowl area (as long as at least one covie remains). You can even help the covies, at the appropriate time.
Be sure to eliminate any threats there before the newcomers are down though, to keep them healthy for the main event. It's also good if you can deal with the passage guards before the newcomers reach you. With this protection concern in mind, try to engineer things so the reinforcements are only triggered when you're down to the last few covies, easy to quickly finish.
A bonus with this method is that the Marines will include either Stacker or Johnson, at random. Your original squad had neither (despite your hearing Johnson's voice at touchdown). Bear in mind though, you'll also be getting a random sergeant in the grav-lift area. As such, you can actually end up with two Stackers or two Johnsons!
NB: if it seems like your initial Marines are all dead but you're not getting reinforcements flying in, it may be that a Marine has got left behind in the previous area back around the corner. Go and check.
Incidentally, having ten Marines survive the grav-lift battle doesn't mean you'll have extras when you arrive on the ship. They'll stand on the lift waiting (see pic), and it'll be an impressive sight, but sadly you'll still only have five guys when you arrive. What a swindle!
Interior checkpointing
Earlier, I mentioned about getting a battle start checkpoint in the entry passage. However, that checkpoint is fully delayable, enabling you to instead get it some place well inside the grav-lift area. There's good potential here for shaping your set-up in a novel way.
If you want to do this, you should initially delay the checkpoint for a few seconds, e.g. by jumping as you go. After that, enemy threat can take over for a while. Depending on where you want to get the checkpoint, you may need to then resume jumping to keep the delay going. Keep in mind though, you'll probably want to get the checkpoint before the covies start firing (e.g. Shade gunners targeting the incoming reinforcements), because active ordnance causes checkpoint delay.
Battle tactics
In my original version of this article I included some tactics talk for handling the waves of opposition coming down from the ship. But it wasn't specific to the extra Marines trick, so I've now formed a separate article for that stuff. See Grav-Lift battle tactics.
History and credits
I'm not sure whether there was some particular place where this extra Marines trick was first advertised. I'd actually noticed sometimes getting an extra bunch of bozos, but had never got around to investigating why it happened. Then in January 2007, fellow cyborg Two Finger emailed, clueing me in on it. After posting my initial account, an HBO post from Simpsons Rule helped me refine my account. And now in 2026, having finally got around to making a tutorial, I've done a fresh revision, pretty much rewriting things.