That's the one where you arrive on the train, right? Yea, thats the hardest fight for me, no question. Shit STARTS with two barons...then the Cacodemons, Pinkies, CyberMancubus...relatively cramped area, not a lot of teleporters or lifts for you to panic and escape with, dont remember if there was a power-up either...the mission 13 stuff is easier cuz they give you such a wide area to run around in, here you're just stuck.
Yep, that's the one. If I recall correctly, I start out by one-shotting the distant Cacodemon with the Gauss Cannon's siege mode. Then I have a few seconds to gather shit nearby before the two Barons (and two Revenants, iirc) drop onto the train platform. It's not long before Imps are also all up in my ass throwing fireballs everywhere. I usually take out the lot of them on the platform before dropping down, by which point more Cacodemons are on my tail, and Lost Souls are bombarding me out of nowhere. More Revenants show up, but shit
really gets real when the Cyber Mancubi appear on the scene. At that point I chainsaw through them, only for the Pinkies to start rushing me down (and more Revanants,
why are there so many Revenants). And when I'm done with -them-, there's another Cyber Mancubus, and two more Barons of Hell, and then a regular Mancubus to round things out. I'm sure there's more that I'm missing. Goddamn, that fight is HARD.