If it’s the Carrier I’m thinking of, where Juvies first spawn and it’s a long, wide area with dirt, and red gas pipes overhead and to the side, I first take out the Juvies quickly. Shooting the Poppers helps as they can explode and kill other Juvies.
I then shoot both overhead gas pipes just as the Carrier approaches them. Make sure you mark the Carrier so your squad will take aim at it. There’s also a heavy weapon I didn’t even see off to the side just before getting to where the Juvies are first triggered. I think it’s a Mulcher.
I would advise using that from far cover once the Carrier is split open. The place where you first enter that area btw is a convenient duck under, and the Carrier won’t go there. BTW, firing a Shock Trap at it’s entryway can keep any Juvies from coming in, if t here are any left.
The Drones when on the crane I used the Markza and did quick pops from cover. I can’t remember the exact sequence between the crane and my final spot on that fight, but I chose on both Experienced and Insane to climb the ladder once the crane was docked, and took out any remaining Drones and the Flock from up there.
The times when the Pouncer comes after hitting the switch, I used the little duck under to get to the other side while my squad distracted it, then came up the ramp a bit to alternate between free firing when it’s distracted, and ducking under. There’s also a Trishot you can carry into that whole area, and another you can get ammo from in a dark cubby hole just up from the first switch you activate. BTW, Flash freezing Pouncers is boss, and you should easily have that by then.
First Riftworm part is easy, as you only have to quickly shoot the holes closed. Knowing what part of it opens first is key, because you want to pummel it right away and close it, preferably after active reloading in prep. The last part where it spawns a Flock is a bit tougher, but there’s a heavy there you can pick up (Mulcher I think), which makes it a lot easier. You’ll of course want to take the low cover available on the railing side once the Flock is in air. When you fall through to where the rocket blast gates are when fighting the Kraken, I used the Markza on the tongues standing near ammo. Two times of 3 quick rounds kills them. I like it better than taking cover because cover firing is slower and it’s scripted to destroy the cover.
The part where the truck gets stuck I like to take cover on the left pillar, then immediately take out the two coming down on the left, then immediately roadie run up onto the left of the upper area, taking cover behind the nearest pod, then leap frogging to another after each kill. Chances are the sniper won’t notice and will still be shooting at your squadmate below.
I then rush the bus they’re in and take cover and kill the sniper. There’s a Hunter or two that come as well, but they are timid at close range as they use splash damage weapons as their primary. Not too hard to take them out if you avoid their lockon. When the Flock comes, that bus is an excellent spot to take on it and the Leeches that come, and especially to take cover from the Carrier’s Cankers it shoots out. The Carrier takes more time than the rest due to having to be near cover to avoid a deadly Canker blast, so tread carefully. Make sure you mark it and the Torque Bows left behind can deal big damage to it’s open belly, provided you’re near cover to dash to. You’ll spend a fair bit of ammo in that fight on Insane.