So, thought about it and there’s a simple way for gearbox to fix the borderlands story, without any retcons or rewrites. Just use the (slightly messed-up) lore that they’ve already created.
So, the story of borderlands 4 would be as follows, with you being a new vault hunter (one of 4-6). Here goes:
You begin at the bottom of a mountain, in dense vegetation, fighting off attacks from various creatures (like apes, big cats, super-fast lizards, etc), and climbing up the slope, until it rapidly becomes rocky and then snowy (with no vegetation). At the top, you enter a cave and find a pedestal, with a space missing in the top.
When you activate the pedestal, your character places a large object in the space, shaped like a cone, with glowing sides. It’s a vault key, and as soon as it clicks into place, an arch like the vault symbol glows in the wall. A doorway opens up and a monster barges through, attacking you. It has four legs and two huge appendages sticking from it’s back, like wings without any membrane, just the bones, and a head covered in short spikes, with two long tusks.
You kill it.
As the monster explodes into a pile of loot, the doorway stays open behind it, and (once you have anything you want) you enter the vault to claim your prize. Inside, the vault has a familiar layout, with a bridge leading to a diamond shape, with a pool surrounded by statues in the center, and in front is a statue holding its hands up, almost cradling a floating object.You highlight the object and the description refers to it as “some weird alien doodad”.
When you take it and exit the vault, a face appears at the top of your screen. It’s the Firehawk, whom you recognise. She congratulates you on looting the vault and informs you that some of her best friends were on their way there and you’ve beaten them to the prize. She invites you to join the crimson raiders as a vault hunter, and help her hunt for more vault treasures. She also promises that her expert on alien technology will help you figure out what you found.
You accept and head back to the start of the map, where Brick, Mordy and Tina are waiting for you, with a ship. Along the way, Lilith explains that she’s been recruiting vault hunters to help with an upcoming war, she’s not sure of the details but “a friend” warned her she’ll need everyone she can get.
When you get to the B team, you speak to them and board the ship, which flies you up to Sanctuary.
Once there, you’re met with the instruction “Talk to Lilith”, and a waypoint that takes you straight to the bridge. The path is linear, with all other routes blocked off. Once there, you see Lilith standing at the controls, alone.
She turns, siren tattoos glinting in the light, and says “Heya, killer. Welcome to Sanctuary 2.”
You hand her the doodad, and she gestures behind you, where Tannis has now walked in. Tannis takes it, her arms exposed and not bearing the tattoos of a siren. She examines the doodad and explains that it is an advanced guardian mind core, like those she’s read about.
“They allow you to access different universes,” she explains, “either more chaotic versions of the same universe, or even alternate timelines where events happened differently.” Tannis looks at Lilith. “I’ve been wanting to find one of these ever since I first read the eridian’s writing about them. I’m hoping there might be an alternate universe where they’re still around and I could interact with them directly. Just think of it.”
Lilith stares at Tannis. “So, there might be a universe where Roland didn’t…”
Ellie walks onto the bridge. “A universe where Scooter isn’t…”
Maya steps out from behind Ellie, joining the others, her siren Tattoos visible. “A universe where Krieg hasn’t…”
Claptrap darts past them and up to Tannis. “A universe where my product line wasn’t WIPED OUT! Think of the possibility.” His voice is that of borderlands 2, not 3.
Tannis frowns at Lilith. “Maybe it’s not worth the risk. The eridians clearly locked these things away for a reason.”
Claptrap waves his arms around. “Awww man. Screw that noise. Let’s use it.”
Lilith looks between Tannis and Claptrap. She pauses for a moment. “I say we use it.”