UPDATE 1.1.5 · LIVE JULY 21, 2026 · EXTENDED TO AUGUST 18 · UPDATED 2 AUG 2026
Vault Breaker is Marathon's first PvE-only mode — an experiment that removes rival squads entirely. You run progressively tougher Vaults inside Cryo Archive against UESC forces, solo or with a crew, and the only thing hunting you is the AI. It arrived with Update 1.1.5 on July 21, 2026 and was built as a two-week test closing August 4 — Bungie extended it to August 18, 2026 citing the volume of feedback the first week produced, and it closed on that date. The mode is no longer available. This page stands as a record of how it worked, and as the best guide to what Season 3's permanent PvE mode is being built from. If you've been curious about Marathon without the PvP pressure, you now have a month rather than a fortnight.
Vault Data is the event currency and the main thing you carry out. It comes in two tiers, earned differently — and the difference matters for how you should play.
Nothing else leaves. Items and gear found during a run do not exfil with you — only Vault Data and designated event rewards. Don't waste run time looting for the main game; it stays behind.
Vault Data has two sinks. You can upgrade the Sponsored Kit itself, making deeper Vault runs more survivable — or spend it in the new Vault Breaker Armory (under the Event section of the Armory tab), which sells gear usable in Vault Breaker and in Marathon's other modes. That second part is the bridge: the event grind can produce equipment your main-mode Runner keeps after the event closes.
Unspent Vault Data does not survive the event. Neither does Sponsored Kit progress. There is no conversion to standard currency, no carry-over into Season 3, and no grace period — when Vault Breaker closes, a full wallet is worth exactly the same as an empty one.
Which makes the final week a different game to the first three. Kit upgrades only pay off if you have runs left to use them on, so once you are inside the last few days the maths flips: stop investing in the kit and convert everything into Armory purchases, because that gear is the only thing that leaves with you. Aim to hit the close at zero.
Early days: kit upgrades, because they compound — a stronger kit means deeper runs, and deeper runs mean consecutive-Vault streaks, which is the only Tier 2 source. Pivot to Armory purchases in the event's back half once your runs are stable. If you only plan a handful of sessions, skip deep kit investment and buy the cross-mode gear directly.
Bungie has confirmed a full PvE mode for Season 3 on September 22, 2026, a date set out in its own Key Dates post — alongside a new Runner Shell, a Perimeter rework, and new enemies. Vault Breaker is the stress test: two weeks of data on whether the AI encounters and the infrastructure hold up without human opponents. Play it as a preview of Marathon's biggest structural bet, not just an event.
If you already main Marathon: yes for the Armory gear, and the Tier 2 streak chase is genuinely tense. If you bounced off Marathon because of third-parties and PvP anxiety: this is the best stretch the game has ever offered you was a free kit, no level gate and no other players, with a clean exit on August 18. The mode's biggest limitation is honest to state: it's experimental, it's one map, and the run variety will be fully explored well before the window closes — the extension gives you more time, not more content.