Boss fights in Borderlands 4 are some of the most intense moments you will face as a Vault Hunter. Each one tests your ability to adapt, whether it is breaking through shields, countering immunity phases, or keeping up with airborne enemies. The key to success is knowing what each boss does, how their mechanics work, and which tactics will consistently bring them down. This guide will walk you through every major boss encounter, from the earliest fights to the climactic showdown with the Timekeeper.

Borderlands 4 Boss Guide: How to Beat All Bosses
Understanding Boss Categories and Mechanics
Borderlands 4 features three distinct boss categories that require different approaches. Campaign bosses drive the story forward and gate your progression, while Vault monsters offer optional challenges with premium rewards. The Weekly Big Encore Boss system lets you respawn defeated enemies through Moxxi's Big Encore Machine for additional farming opportunities.
Most bosses follow predictable patterns once you understand their core mechanics. Immunity phases require specific actions like throwing Locust Canisters, while aerial enemies demand positioning and patience. Here's what separates successful vault hunters from frustrated ones:
tip
Always prioritize clearing minions during boss fights - they provide Second Wind opportunities and prevent overwhelming pressure.
Early Game Bosses
Warden Scathe
Your first encounter in the Guns Blazing mission teaches essential mechanics. Scathe fires beam attacks while Synth bots maintain pressure. Use the elevated walkway on the left side for cover, clear adds between beam bursts, then punish Scathe during his recovery windows.
Splashzone
This Ripper boss in the Recruitment Drive mission demonstrates melee combat principles. His mechanized arm creates devastating ground slams, but the cramped bandit camp offers ledges for tactical positioning. Maintain distance, use elevation to reset aggro, and burst during his recovery animations.

Borderlands 4 guide: All campaign ...
Spymaster Horace
Horace combines Scathe's ranged attacks with shield mechanics. His energy barrier melts under Shock damage, triggering a phase transition where he switches to scythe-based melee pursuit. Break the shield efficiently, then strafe his rushes while maintaining damage output.
warning
Don't waste ammunition on shielded enemies - always match damage types to defenses for maximum efficiency.
Mid-Game Bosses
The Oppressor
This flying fortress in A Lot to Process requires fundamental changes to your approach. Grenades and shotguns become useless against its altitude, while the green glowing weak spot on its underside demands precision. Use arena machinery to maintain elevation and dodge homing missiles.
Bio-Bulkhead
The One Fell Swoop encounter introduces Locust Canister mechanics. This mutated beast maintains immunity until you grapple canisters and throw them accurately. The two end pillars provide cover, but timing your vulnerability windows becomes crucial for success.

Borderlands 4 Rush the Gate Walkthrough
Idolator Sol
Sol concludes the Fadefields arc with layered mechanics: pillar summoning, grunt feeding, and corrupted energy zones. He drops multiple pillars including a green one containing the essential Locust Canister. Meanwhile, spawned grunts must die quickly before Sol devours them for health restoration.
Advanced Bosses
Skyspanner Kratch
This giant bat boss punishes ammunition waste with limited arena supplies. Multi-hit sonar screams and swarming minions create overwhelming pressure. Take cover during screams, prioritize adds for Second Wind opportunities, and maintain disciplined shot placement.
Vile Lictor
One of the Timekeeper's Lieutenants, Lictor demands exceptional reflexes. His Hundred Hands ability spawns tracking projectiles requiring immediate evasion. Spectral Walls come in two variants - ground-traveling walls need jumping, while segmented walls require gap identification.
Driller Hole
This underground artillery specialist bombards areas with Incendiary damage while Rippers pressure your flanks. The central structure becomes your lifeline - circle it to break line of sight, peek for damage windows, then rotate as shells impact.
important
After defeating Driller Hole, pull all levers at the machinery's top and destroy ceiling pipes to save the NPC Quent.
Endgame Bosses
Callis the Ripper Queen
Callis showcases erratic movement with multiple attack patterns. Her Fire Orbs travel along the ground before returning, Drone Mines explode on timers, and bomb-carrying Rippers add chaos. After depleting her first health segment, Laser Nets immobilize you while dealing damage.
Moon-Maddened Callis
The Elpis rematch restricts your movement to floating rock chunks. Getting knocked off requires immediate grappling to return to the arena. During phase transitions, wide nets hang overhead - stay low and dodge bombs while managing the cramped space.
The Timekeeper
The campaign's climactic encounter features three health segments and reality-warping abilities:
Phase One Mechanics:
- Golden Wall: He shields while mechanisms attack - use grenades with splitting or lingering effects
- Blinding Blast: Golden ground glow precedes a flash - turn 180 degrees to negate
- Aerial Assault: Phase transitions toss you skyward - glide to safe spots while dodging projectiles
Phase Two Escalation:
- Fragment Scatter/Matrix: Missiles explode into energy grids crossing the arena
- Bounce and Blast: Melee swipes suspend you for energy blast vulnerability
- Aerial Annihilation: Ground becomes damaging - grapple floating ledges while avoiding beams
Optional Vault Monster Challenges
Inceptus (Fadefields Vault)
Target shoulder and knee plates with your grappling hook to expose pustules. During cocoon phases, grapple lanterns and shoot the base for critical damage. Dash sideways to avoid tail stabs, then capitalize on stun windows.
Radix (Carcadia Burn Vault)
Focus fire on the glowing red throat while maintaining distance from ground slams. When shockwaves chain across the arena, glide over them or find safe rocks. The arena becomes a lightning-filled obstacle course requiring constant movement.

Borderlands 4: All Optional Vault Bosses
Origo (Terminus Range Vault)
This dual-element boss alternates between Incendiary and Cryo breath attacks. Target back crystals while he's grounded, use your grappling hook on ground vents to launch airborne, then glide over hazard zones during his aerial dives.
Combat Fundamentals Across All Encounters
Every boss fight rewards fundamental combat principles. Match damage types to defenses, prioritize add clearing for Second Wind safety nets, and use environmental cover strategically. Ammunition management becomes critical in longer encounters, while positioning determines survival against area-of-effect attacks.
The grappling hook serves multiple purposes beyond mobility - environmental interactions, weak spot targeting, and arena traversal during immunity phases. Master these mechanics early, and later boss encounters become tactical puzzles rather than overwhelming challenges.
Whether you're facing your first Warden or preparing for the Timekeeper's reality-bending finale, these strategies will transform boss encounters from frustrating roadblocks into exciting loot opportunities. Each victory brings you closer to mastering Kairos and claiming your place among legendary vault hunters.
For more Borderlands 4, take a look at our How to Respec Skills guide.

