Bungie launched an experimental PvE mode called Vault Breaker in Marathon on July 21, 2026, as part of a mid-season update [1, 2, 3]. The mode takes place in the Cryo Archive, where players face progressively harder vaults over multiple runs in a roguelite format [1, 2, 3].
Vault Breaker supports solo, duo, or trio play styles, allowing flexible team compositions for tackling the vault challenges [1, 2, 3]. Players collect Vault Data during runs, which can be spent upgrading a specialized Sponsored Kit or purchasing gear usable in other Marathon modes, though this gear cannot be used inside Vault Breaker itself [1, 2, 3].
Bungie explained, "Vault Breakers utilize hit-and-run tactics to master the secrets of the Marathon’s Cryo Archive. They travel light and target the Archive’s many vaults in search of valuable loot and deeper access throughout the deck" [1]. The Sponsored Kits start weak, offering only a single standard weapon and limited equipment. As players earn Vault Data, they unlock different upgrade paths focusing on weapon quality, survivability, or expanding implants and cores, with the choice left to the player [3].
There are two tiers of Vault Data: Tier One is earned from vaults and killing UESC Commanders and must be extracted, while Tier Two comes from solving consecutive vaults and extracting successfully [3]. Vault Breaker’s experimental phase is limited to two weeks, running from July 21 through August 4, 2026 [1, 2, 3].
A full rollout of the Vault Breaker PvE mode is planned for Marathon Season 3, which begins September 22, 2026, though the exact date for the mode’s integration is not yet certain [3].
