Borderlands 4 Complete Walkthrough: Tips, Builds & Secrets

Borderlands 4's campaign spans four distinct regions on planet Kairos and takes roughly 25-30 hours for the main story. This walkthrough covers the critical path plus the side content that's actually worth your time.

I've played through the campaign four times now - once with each base Vault Hunter - and I keep finding new things. The branching dialogue system isn't Mass Effect, but three choices toward the end meaningfully change what happens. I'll flag those.

Region 1: Ironhold (Levels 1-12)

This is the smuggler's moon slums I covered in the beginner guide. Quick recap of the critical path: join the Crimson Resistance, sabotage Order outposts, defeat the Order Enforcer, and secure the Resistance's foothold in the city.

The main side content worth doing here:

The Lost Transmission (Level 8): Elena sends you to recover a data cache from a crashed Resistance ship. The cache contains intel about the Timekeeper's Bolts - the cybernetic implants controlling the population. This quest gives you a class mod choice at the end and the lore is actually relevant to the ending. Not skippable if you care about the story.

Arms Race (Level 10): Repeatable arena combat in the Ironhold Colosseum. 5 waves of increasing difficulty. Rewards change daily - check the bounty board for what's on offer. The day-one legendary pool includes a Jakobs sniper that carried me through the next two regions.

Hidden Typhon chest locations in Ironhold: behind the waterfall in the Slums (east side), on the rooftop of Elena's safehouse (climb the scaffolding), and inside the collapsed tunnel near the Colosseum entrance (requires a grenade to clear the rubble).

Region 2: The Verdant Expanse (Levels 12-22)

The second region shifts from urban to overgrown wilderness. Formerly a nature preserve, now overrun by mutated wildlife and Order patrols. The aesthetic is a welcome change from the grimy slums.

Main mission arc: reach the Resistance's jungle outpost, reactivate an old Eridian communications relay, and fend off an Order assault on the outpost.

Boss: the Corrupted Vault Beast (see boss guide for full strategy). Bring shock + incendiary, stay off the electrified floor in phase 3.

Critical side quest here: The Bolts That Bind (Level 16). A scientist at the outpost has developed a way to temporarily disable Bolts in captured civilians. You need to infiltrate an Order re-education camp and test the device. The camp has three objectives: disable the signal jammer (rooftop), extract the prisoner logs (basement), and test the Bolt disruptor on three prisoners (ground floor).

This quest is important because it introduces the Bolt Disruptor grenade mod - a unique item that stuns Order soldiers for 3 seconds on hit. It works on every Order enemy including bosses. I keep this grenade in my inventory for the entire campaign. The stun duration doesn't scale with level, but the utility is irreplaceable.

If you're hunting collectibles, the Verdant Expanse has six Eridian Glyphs scattered across the treetop villages. The Glyphs unlock lore about Kairos's original Eridian inhabitants and are tracked in your challenges menu. Finding all six in this region unlocks the "First Contact" artifact, which boosts Eridium gains by 15%.

Region 3: The Forge (Levels 22-32)

Industrial hellscape. The Timekeeper's manufacturing district where Bolts are produced and The Order's synthetic soldiers are assembled. This is the darkest region - literally and tonally. Bring a weapon with a flashlight attachment or crank your gamma.

The main mission here has you infiltrating the Bolt manufacturing plant, overloading the reactor, and fighting your way out during the meltdown sequence. The escape sequence has a 10-minute timer and some genuinely tricky platforming sections with the grappling hook. If you haven't been practicing traversal, this section will frustrate you.

Boss: The Forgemaster, a giant industrial mech with four interchangeable weapon arms. Each arm cycles every 60 seconds: flamethrower, railgun, missile pods, and shock cannons. The flamethrower and shock cannon phases are the most dangerous. During railgun phase, the boss stands still to aim - free damage window. During missile phase, the missiles can be shot down.

After clearing the Forge, you unlock vehicle customization at the Resistance garage. The hover bike upgrades (speed boost and side-mounted weapons) are worth the credits. The buggy's armor upgrades make certain story segments less painful.

The Choice at Level 28: Elena asks whether to broadcast the Bolt-disabling signal city-wide or use it strategically. City-wide frees more civilians but alerts the Timekeeper earlier, making later missions harder with increased Order presence. Strategic keeps things quieter but fewer civilians are freed. This affects the ending - the city-wide choice gives you more allies in the final battle.

Region 4: The Spire (Levels 32-35+)

The Timekeeper's seat of power. A massive tower complex with three distinct zones: the Outer Ring (garrison), the Inner Sanctum (elite guards), and the Observation Deck (final boss arena).

The Outer Ring is a combat gauntlet. Dense enemy packs, multiple miniboss encounters, and limited ammo restocks. Pack ammo regen gear or a Tediore weapon for infinite ammo (Tediore weapons regenerate ammo slowly in BL4, a new feature). This section takes about 45 minutes with no checkpoints between fights.

The Inner Sanctum has puzzle elements - you need to redirect power conduits to open doors while fighting waves of Order Elites. The puzzle isn't hard but the combat + puzzle combination stresses some players. If a conduit is sparking, it's active. If it's dark, redirect power to it. There are three conduit puzzles total.

The Choice at the Observation Deck: Before the Timekeeper fight, you encounter a civilian with a Bolt implant who begs you not to trigger the city-wide disruption (if you chose that). The disruption could kill them. You can spare them (they help in the fight, providing occasional healing) or activate the disruption anyway (all civilians freed, but this civilian dies). This is the second ending-affecting choice.

Final boss: The Timekeeper, covered in detail in the boss guide. Post-fight, you get your ending based on the two choices above plus a third choice about what to do with the Timekeeper's Bolt control mainframe. Destroy it (all Bolts deactivated, chaotic transition of power), repurpose it (Bolt tech used to help rebuild), or leave it (status quo maintained by the Resistance). Each ending has a different epilogue cutscene and unlocks different post-game content.

After the credits, Mayhem Mode and Eridian Rifts unlock. The real game begins.