How to Complete the Line in the Sand Quest in Arc Raiders
While the objectives sound vague at first glance, the quest is actually linear once you understand the correct locations. Most steps trigger simply by reaching specific points of interest, meaning no complex puzzles or item farming is required. The main challenge comes from map navigation and knowing where to go next.
This guide breaks down every step in order so you can complete the quest efficiently in a single raid if desired.
Quest Overview and Context
In Line in the Sand, Celeste asks you to investigate a derailed train carrying vital supplies from Stella Montis. According to recovered data, the shipment contained advanced thruster valves intended for Marano Station, but the train never arrived. The implication is that the derailment was not accidental, suggesting internal sabotage or organized theft.
The mission unfolds entirely within the Buried City map and involves four sequential investigation points:
Locate the derailed train
Investigate who orchestrated the robbery
Determine where the thruster valves were hidden
Search a merchant apartment basement for final evidence
Each step builds on the previous one, gradually revealing a broader conspiracy involving intercepted logistics and hidden supply chains.
Step 1: Investigate the Derailed Train
Your first objective is to locate the train that never reached Marano Station. This wrecked train is your entry point into the investigation.
Head to the western-central section of Buried City, in the area between key landmarks such as Warehouse and Piazza Roma, just south of Marano Station. You will find several derailed blue train cars scattered along the tracks.
When you approach the wreck site, the objective will automatically update without requiring interaction. There is no need to search specific containers or loot anything here; proximity alone is enough to trigger progression.
This step is intentionally simple and serves as an introduction to the investigation chain. Once complete, your next objective will point you toward a nearby structure to continue the trail.
Step 2: Identify Who Orchestrated the Robbery
After examining the train wreck, your next destination lies slightly east of the crash site.
You will need to locate a small elevated tower structure in the same general district. The tower is visually distinct and usually stands alone, making it easier to identify against the urban ruins.
Once you reach the tower:
Climb or mantle into the structure
Search the interior corners carefully
Interact with the hidden clue item inside
In most cases, the interaction reveals a Marano Market Business Card, which serves as critical evidence linking the train incident to a larger operation. This item does not require extraction mechanics; it simply advances the quest when picked up.
This step strongly implies that the derailment was orchestrated rather than accidental, pointing toward coordinated theft involving merchant-level access or insider knowledge.
After collecting the clue, the quest will update again, directing you toward a ruined commercial zone further north.
Step 3: Locate Where the Thruster Valves Were Stashed
The third objective takes you deeper into the Buried City ruins. From the tower location, travel northward past major landmarks such as the Library and Hospital zones until you reach a broken market district.
This area is recognizable by collapsed buildings, scattered debris, and partially intact storefronts. It is often referred to by players as the Market Ruins.
Approaching the correct zone automatically triggers the next quest update. You do not need to interact with any specific object at this stage-simply entering the area completes the objective.
Narratively, this step suggests that the stolen thruster valves were moved quickly after the train incident and hidden in a secondary storage site within the city.
Be cautious while traversing this area, as it is a common hotspot for ARC patrols and other players depending on server activity. While combat is not required for quest completion, survival is necessary to continue progression smoothly.
Once the objective updates, your final destination will be revealed on the eastern edge of the map.
Step 4: Search the Merchant's Apartment Basement
The final step of Line in the Sand brings you to a residential-commercial building located in the eastern sector of Buried City. This area sits near the edge of the map and is slightly separated from the previous ruins, requiring a longer traversal.
Upon arriving at the building:
Enter through the main ground-level entrance
Move through interior rooms until you find a vertical access point
Use the zipline leading downward into the basement level
This descent is a key part of the quest design, as it transitions from surface investigation into a hidden underground storage area.
Once in the basement, you will find stacked boxes along the walls. Approach the marked interaction point near the crates and take a photograph or scan of the evidence (depending on your control settings).
This final interaction completes the quest objective chain.
After capturing the evidence, the mission is officially finished. You can safely extract or continue playing, but no further objectives are required for Line in the Sand.
Tips for Completing the Quest Efficiently
Although the quest is relatively straightforward, a few practical considerations can make completion smoother:
1. Run a lightweight loadout
Since no high-risk boss fights or extraction requirements are tied to quest items, many players choose a free or low-value ARCR Items to minimize loss risk.
2. Follow a north-to-east route
Efficient routing matters. After the train, move east to the tower, then north to the ruins, then east again to the final building. This minimizes backtracking across the Buried City map.
3. Expect minimal combat but remain alert
While the quest itself does not require combat, ARC enemies and other raiders can interrupt traversal, especially around the Market Ruins.
4. No item extraction needed for quest progress
Most steps are location-triggered rather than inventory-based. The only persistent progression element is the business card clue, which updates the quest internally.
Rewards and Quest Significance
Completing Line in the Sand rewards players with crafting and progression ARC Raiders Materials such as Exodus-related components. More importantly, it advances the broader narrative tied to Stella Montis and the underlying logistics collapse within the game world.
From a lore perspective, this quest reinforces a central theme in Arc Raiders: systemic sabotage and fractured supply chains following the Exodus collapse. The investigation hints at coordinated interference with critical infrastructure rather than random ARC disruption alone.
It also sets up follow-up missions in the same quest chain, continuing Celeste's investigation into deeper conspiracies within the Buried City and beyond.
Final Thoughts
Line in the Sand is a classic exploration-based quest that emphasizes environmental storytelling over combat or mechanics. While its objectives may initially appear vague, the structure is actually quite linear once the correct path is known.
The key to success is simple: follow the map progression-train wreck, tower clue, market ruins, basement evidence-and the quest resolves cleanly without complications.
For players working through the Riven Tides content, this mission acts as a narrative bridge between early investigation quests and more complex multi-zone objectives later in the chain.