Marathon: How to Complete Data Reconstruction 2 – Fast Dire Marsh Route

The Short Answer

Data Reconstruction 2 is a two-part NuCaloric job on Dire Marsh: download the harvest logs from the terminal in Algae Ponds, then hack three Data Repositories along the AI Uplink catwalk. The Algae Ponds terminal is on the second floor, in the room with the big glass display — the building itself is the bright cyan one, which is your best navigation cue in the fog. The three Repositories are small box terminals spaced along one continuous catwalk; approach from the east to dodge most UESC patrols. In my runs, objective progress persisted across raids, so a bad wipe at the Uplink does not cost you the Algae Ponds half. Clean run: 8–12 minutes.

Dire Marsh in Season 2: Read This First

Verified July 2026. Marathon is on Season 2: Nightfall, live since 2 June 2026 and running to 22 September 2026, 17:00 UTC. The current build is Update 1.1.5, shipped 21 July 2026 with the limited-time Vault Breaker PvE mode (21 July – 4 August, set in Cryo Archive).

The single biggest change for anyone routing Dire Marsh:

• Night Marsh exists now. It is a nighttime variant of Dire Marsh built around darkness and heavily reduced visibility — the same geography, played closer to survival horror.
• The two rotate every 90 minutes. Bungie ran both simultaneously for the first week of the season, then set them to alternate availability on a 90-minute cycle. So “queue Dire Marsh” is no longer guaranteed at any given moment.
• Most existing Dire Marsh contracts work on either version. Bungie’s Season 2 material indicates contracts tagged to Dire Marsh generally function on Night Marsh too, with some new MIDA and Traxus contracts being Night-exclusive. In practice that means the route below still works when Night Marsh is up — you just cannot see nearly as far.
• Dire Marsh is also in the daily-rotating Duos Queue, alongside Perimeter, Night Marsh and Outpost.

One honest caveat before the walkthrough: the 1 June wipe cleared Runner level, faction levels and upgrades, contracts, Credits and Vault contents, and Bungie reworked progression for Nightfall without publishing a contract-by-contract changelog. Only the first Priority Contract per faction carried over. So we cannot independently verify the exact current naming or step order of this chain in Update 1.1.5. What is unchanged is the map — the POI layout, the building interiors and the landmark chain below — and that is the part that actually saves you runs.

Contract Basics

• Faction: NuCaloric
• Map: Dire Marsh (and, when it is up, Night Marsh)
• Objective 1: Download harvest logs from the terminal in Algae Ponds
• Objective 2: Hack three Data Repositories at AI Uplink

The thing worth internalising: these two tasks did not have to happen in the same raid in my runs — progress stuck between them. That changes how you play it. If Algae Ponds goes clean but the lobby is boiling, bank what you have and extract rather than dying on the catwalk with nothing.

Loadout

This is not a hard combat contract, but the AI Uplink catwalk turns into a mini-arena. What works:

• Primary: a medium-range rifle or burst weapon for clearing patrols on the catwalk.
• Secondary: a fast-handling SMG or shotgun for the Algae Ponds stairwell and interior rooms.
• Throwables: a couple of frags or proximity mines for area denial while you are rooted in a hack.
• Healing: two to three med kits minimum.
• Bag: keep it light. Stowing your weapon between fights gives you noticeably more sprint speed, and open ground on Dire Marsh is where you die.

If Night Marsh is the live rotation when you queue, add a light source or plan for close-range engagements — the sightlines that make the catwalk dangerous in daylight cut both ways at night, and your medium-range rifle does much less work.

Objective 1: Harvest Logs at Algae Ponds

Find the building

Algae Ponds is a named POI, so your map labels it. In-world, look for the bright cyan exterior — that colour is the fastest way to identify it through the fog, and it beats trying to navigate building-by-building. In Night Marsh the cyan reads much darker; go by the map label and the pond structures instead.

Get upstairs

• Enter at ground level, immediately check for patrols and ticks, clear anything close.
• Find the main stairwell — a plain flight of stairs, not a ladder or elevator.
• Go to the second floor. Do not sweep the ground floor rooms; the objective terminal is never down there.

The glass-display room

On the second floor, look for the room with a large glass display dominating one wall — think observation window. The harvest log terminal is inside. Hold interact (E by default) until the download completes.

If you get pushed off mid-download: clear the threat, return, hold again. Progress completed without any reset in every run I did.

Objective 2: Three Data Repositories at AI Uplink

Approach from the east

The eastern approach is the whole trick. Leave Algae Ponds by its quietest exit, swing around the outer edge of the map, and come onto the Uplink from the east side. Cutting straight through the central patrol density is how most of my early attempts ended.

Hack them in a line

The Repositories are small box-like terminals mounted on the catwalk structure — data nodes, not full computer stations. From the eastern entry:

• Step onto the catwalk and clear nearby AI and ticks first.
• The first Repository sits very close to the eastern end.
• Hold interact to start the hack; there is a short channel.
• The second and third are spaced along the same continuous path, always on attached structure — never tucked in side rooms.

If you find yourself dropping off the main catwalk or hunting side platforms, you have overshot.

Surviving the channels

• Clear first, hack second. Sweep angles, check beams and the space underneath for ticks, listen for footsteps.
• Deny the approach. A proximity mine or frag down the main lane either kills a pusher or warns you one is coming.
• Face the danger. You can break the channel at any time to fight, so orient toward the most likely angle.
• Heal between nodes. There is no prize for speed if you die on Repository three.
• Do not chain all three through gunfire. Hack one, reposition, reset, continue.

The Full Route

1. Spawn → Algae Ponds. Weapon stowed, cover-to-cover, straight to the cyan building.
2. Clear and download. Second floor, glass-display room, harvest logs.
3. Rotate east. Quiet exit, outer edge of the map, approach AI Uplink from the east.
4. Hack three Repositories in order along the catwalk, healing between each.
5. Extract. Break line of sight immediately and path out. Do not tour the arena for loot with the contract banked.

8–12 minutes in a normal lobby. Add time for third parties — the catwalk is a magnet.

Troubleshooting

• “I can’t find the Algae Ponds terminal.” You are not on the second floor, or not in the room with the large glass display. Keep circling the upstairs corridor until you see that window.
• “I hacked a node and nothing completed.” You need all three. Watch the tracker tick after each one.
• “UESC patrols kill me every approach.” Take the eastern line and skirt the map edge. If the run is too hot, bank Algae Ponds and leave.
• “I died after one objective — do I redo it?” In my runs each completed objective persisted across raids. You should only need to finish what you missed.
• “I queued and got Night Marsh.” Same geography, far less visibility. The route still holds; the eastern approach matters even more because you will not spot campers at range.

Where This Sits in NuCaloric

Data Reconstruction 2 pays NuCaloric standing plus Credits, healing consumables and crafting materials — exact reward values shift with balance passes, so treat any specific number you see as community-sourced. It is one link in a longer chain; if you are starting NuCaloric fresh after the wipe, our Introducing: NuCaloric fast route covers the entry contract. Materials from this run feed straight into faction upgrades — the best faction upgrades guide is where to spend them, and the Marathon hub collects the rest of our patch and contract coverage.

FAQ

Do both objectives have to be done in one raid?

No. In my runs, progress on each objective persisted across raids, so you can split Algae Ponds and AI Uplink across two sessions if a lobby goes badly.

Does this contract work on Night Marsh?

Bungie’s Season 2 material indicates existing Dire Marsh contracts generally function on Night Marsh as well, with some new contracts being Night-exclusive. The POIs are in the same places; visibility is the only real difference.

Why is Dire Marsh sometimes unavailable?

Since the first week of Season 2, Dire Marsh and Night Marsh alternate availability every 90 minutes. Dire Marsh also appears in the daily-rotating Duos Queue.

Did my Data Reconstruction progress reset?

If you played Season 1, yes — the 1 June wipe cleared contracts along with Runner level, faction levels, Credits and Vault contents. Only the first Priority Contract per faction carried over.