The spooky season has arrived on the frontier. Borderlands 4 has launched its limited-time "Horrors of Kairos" seasonal mini-event, bringing environmental hazards and specific legendary drops to the loot pool. The event is live now and runs through November 6, 2025.
Blood Rain and Boss Fights
Gearbox is keeping this event tight and focused. From October 23 to November 6, the atmosphere on Kairos shifts drastically during world boss encounters. Players will face "terror-inducing blood rain," a mechanic that veterans of the franchise might recognize as a nod to previous Halloween-themed debuffs that impact aim and handling.
While mini-events don't usually overhaul the entire game, the visual and mechanical shift adds a nice layer of tension to the standard boss grind. If you're running a build that relies on precision critical hits, you might need to adjust your loadout to compensate for the terror effects.
What is the new Legendary Loot?
The main reason to jump in, as always, is the gear. Two new Legendary items have been added specifically for this event:
- Murmur (Assault Rifle): A Tediore manufacturer weapon. Tediore throws are often hit-or-miss depending on the tracking AI, but a dedicated event legendary usually boasts a unique reload effect that makes it worth the slot.
- Skully (Grenade Mod): Details are scarce on the damage scaling, but expect tracking mechanics or massive AoE potential given the event's theme.
New SHiFT Code for Cosmetics
Alongside the gameplay updates, there is a new SHiFT code available for everyone. This unlocks a specific Vault Hunter Head and a Weapon Skin to match the event's aesthetic. The code expires on December 31, 2030, so you have plenty of time to redeem it, but you might as well grab it now.
Code: 3S6BB-ZXT93-KRT3W-BT3T3-JW6TZ
You can redeem this via the in-game Social menu or the SHiFT website. The event itself wraps up on November 6, so you have about two weeks to farm for a God-roll Murmur before it potentially disappears from the drop tables.