Much like in The New War, Kahl-175’s Junk Run mission tasks Warframe players with rescuing five Ostron Prisoners held by the remnants of the Narmer. There are five fixed spawns for Ostron Prisoners in the Junk Run mission, and, like in The New War, players have to track them down even in the hidden corners of the map.
Finding all five Ostron Prisoners awards players with 15 Stock, a currency that the Tenno can exchange for Chipper in Kahl’s Garrison for Archon mods, Styanax Blueprints, weapons, and customization items. Finding the five Ostrons isn’t the only opportunity to gain Stock, however, since there are also a series of miscellaneous objectives that award the currency.
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Here are the locations for all five Ostron Prisoners in Warframe’s Junk Run mission for Kahl-175.
All five Ostron Prisoner locations in Junk Run
First location: In the room with the Deacons
The first Ostron Prisoner spawns in the room where you can fry the Deacons with the Arc Mines. After clearing the area, head toward the objective marker on your map and hug the left side to spot this Ostron Prisoner (as well as two possible locations for Grineer Genestamps). Don’t go through the checkpoint just yet, though: there are two more Ostron Prisoners in a nearby area. Enter the passage on your left and prepare to free them.
Second location: In a small room after the Deacons
From the first Ostron Prisoner, make a left and enter the tunnel just past the tree (which may hold a Genestamp). From there, head inside and look for this Ostron Prisoner just ahead of you. This isn’t the last Ostron Prisoner in the room, however.
Third location: Hidden nook within the room with the Deacons
From the second Ostron Prisoner, take the door on your left side and keep on following the room until the end, which should allow you to climb onto a ledge. From there, head straight until you can see this Ostron’s cage to set them free. Don’t remove the barrier in the Deacon room until you’ve rescued these three Ostrons. This is just nearby the Somachord tone and a dead Grineer.
Fourth location: By the Thumper Parts
This prisoner is right next to the Thumper Parts, which should appear on your map as soon as you obtain the Hellion Pack from a fallen Grineer. Follow the icon that appears (or take the right after picking up the jetpack) to spot the room with the Thumper Parts and this helpless prisoner right next to it.
Fifth location: In a small room with a waterfall before opening the bridge
As you near the end, the game will task you with opening an energy barrier that leads to a bridge. When that’s the case, backtrack into the previous room and hug the right to reveal a hidden room with a waterfall and a few Sentient enemies. The last Ostron you need will be by a set of stairs on the left side of the room.
After you’ve found all Ostrons, you can finish the mission and extract to get your 15 Stock. If by any chance you missed any Ostron Prisoners, however, you can try again as many times as you want.