Path of Exile 2 patch 0.5.4b overhauled boss fights across the board

Grinding Gear Games dropped patch 0.5.4b for Path of Exile 2, and it's almost entirely focused on boss improvements — from stun immunity windows to visual telegraphing, phase transitions, and outright disabling problematic mechanics.

Tor Gul, the Defiler lost most of its stun and freeze immunity windows, making crowd-control builds far more viable against it. The Vessel of Kulemak got the most extensive rework: a stuck-after-Teleport-Slam bug is fixed, the minion-summoning skill in the final phase is disabled entirely, and Volatiles now spawn in spaced-out bursts to give players more time to actually damage the boss. A checkpoint revival bug — where killing Vessel of Kulemak for the first time wouldn't put players in a fresh instance on revive — is also squashed. The Arbiter of Divinity now guarantees voicelines on notable skills with less variance, so players can reliably learn which line signals which attack; Divinity Clones in phase two have a significantly larger hitbox; and attack windows between combos are wider with better visual telegraphing and reduced target-tracking aggression. The Arbiter of Ash got a quality-of-life fix too: the voiceline for his lane-of-fire skill now plays at the start of the move rather than after he's already airborne, and players get more time to reach the first Flame Seed in the Large Laser combo. Phya, Sentinel of the Cradle in The Matriarch Halls saw projectile frequency and count cut from the Generator, chilling ground removed from those projectiles, and the Generator stops firing entirely during Gravity Well and Turret Sunder phases. The Gravity Well phase now correctly punishes players who don't reach safe zones — previously the corner spheres could be used to cheese it. It That Was Esh had a phase-advancement failure bug fixed, and the Arbiter of Divinity no longer drops loot in unreachable spots; defeating it also re-enables the exit elevator.

Path of Exile 2 is currently in early access, and Grinding Gear Games has been iterating rapidly on endgame boss encounters following community feedback that several fights felt unfair or poorly telegraphed. Boss design in the Path of Exile series has always leaned toward high difficulty, but the early access period has given the studio real-time data on where players are hitting walls — and patch 0.5.4b reads like a direct response to that feedback across multiple encounters simultaneously.

The sheer volume of boss-specific fixes in a single patch suggests GGG is treating endgame encounter polish as a priority heading into whatever comes next in the early access roadmap. Community reaction will likely focus on the Vessel of Kulemak and Arbiter of Divinity changes, both of which were frequent complaint targets on the Path of Exile 2 subreddit and official forums.