Sentinel Firing Cores are a rare upgrade material in ARC Raiders , mostly obtained by destroying Sentinel turrets in specific open-world zones and looting their remains afterward. They can also very occasionally drop from certain ARC machine husks in the same areas.

Main farming spots

  • Dam Battlegrounds – Research & Administration Building
    • Go to the big central building on the Dam Battlegrounds map; a Sentinel turret frequently spawns on the south staircase / outer corner of the building, scanning the area below.
* Destroy the turret, then loot its body or the ground below where the core can drop; this is widely considered the most **reliable** Sentinel Firing Core spot.
  • Buried City – rooftops and key buildings
    • Check rooftops and high ledges around major buildings like the Town Hall, Hospital, and Research buildings , where Sentinels can spawn guarding loot.
* After killing them, watch for the core falling off the roof or ledge so you do not miss the drop on the ground below.
  • Acerra Spaceport – launch towers & hangars
    • Sentinels can appear around launch towers and hangar entrances , usually protecting high‑tier ARC loot.
* This area is harder but has a good chance to reward cores alongside other end‑game components.
  • Blue Gate – above central checkpoint
    • Spawns are rarer, but you can sometimes find Sentinels above the large central checkpoint or near lookout towers and a big antenna structure.
* Treat Blue Gate as a supplemental spot rather than your primary farming route due to the lower spawn rate.

Non‑Sentinel core sources

  • Arc Courier Husks
    • Damaged ARC machines (“courier husks”) scattered around Dam Battlegrounds and Blue Gate have a small chance to drop a Sentinel Firing Core as part of their random high‑end loot pool.
* While not as consistent as turrets, looting every husk along your route slightly boosts total cores per run.

Suggested farming loop

  • Start each run at Dam Battlegrounds – Research & Administration Building, clear the inside, check the south staircase turret , and loot any Arc Courier Husks nearby.
  • If no Sentinel spawns or you do not get a core, extract, reload a new instance, or swap maps (e.g., to Spaceport or Buried City) rather than waiting, since Sentinel spawns are randomized and reset with instance changes.

Why you need the cores

  • Sentinel Firing Cores are used to upgrade important workstations and gear tiers (such as progressing toward higher‑tier crafting or gunsmith levels), so you typically need several of them, making efficient farming routes valuable.

Information gathered from public forums or data available on the internet and portrayed here.