Follow Revas down the hall and off the ship. After Revas disappears, head into the control area and head to the right. Press the terminal you find there.
Using the terminal sends a drone to your location to check out what's going on. Hide behind the crates or the large computer bank next to the terminal, then stealth kill it when the drone comes.
Grab the drone's gun and put a few bullets into the low glass beside the door the drone came through. You should see holes in the glass.
Now you can go through into the adjoining corridor.
Bounty! Go through the glass and turn right. You'll see the orange Bounty Card No. 7 just ahead.
Backtrack and climb the stack of crates near where you entered, then use Y to grab the handholds above. You can hand-over-hand climb across to the vent just ahead.
After a cutscene, take the corridor to the right. At the end, you can hang from the ledge to get around the vertical shaft. You'll get another cutscene at the other end.
On the other side, follow the corridor to find a nanomed cartridge and machine. Heal up if you need to, then look to the right for a ladder to descend.
At the bottom, continue down the corridor and find the shadows near the crate. You'll hear an announcement that lets you know the Dark Athena's crew is on to you, and a drone will come patroling by a second later. Kill it.
Get back to your hiding place. There's another drone down at the far end of the hallway. Wait for it to turn around, then follow it and take it out silently. Take the ladder down.
At the bottom, you'll have to shimmy around the vertical shaft again. When you get to the other side, you'll see another cutscene.
Turn back around and head to the shaft. Drop down and open the hatch. You'll kill the merc you just saw pass you, and get new weapons: the Ulaks.
Achievement Alert! You'll also get the Ulaks! Achievement here.
You're entering the cargo bay next. You can climb the ladder just ahead and attack the bay from above, or you can go through the door to the left. It's swarming with drones, however, so you'll need to move carefully.
Achievement Alert! Net the Stealth Master Achievement by crossing the entire cargo bay without being noticed.
TIP: The key to successfully stealthing your way through the cargo bay is to be careful when you engage drones. There are a lot in the area and they'll often see you murdering one of their cohorts. However, there's plenty of darkness, so if you can just walk past them, that's your best bet.
Bounty! Climb out of the control room by the ladder and turn right. From here, you can drop down onto a raised section of the cargo bay floor. You'll see Bounty Card 9 waiting for you just below your location.
Bounty! Return to the roof again and look up. You'll see hang rails leading around to the left and the right around the sides of the cargo bay. Go around to the left to find Bounty Card 49. Bounty Card 34 is at the end of the right hangrail.
Make your way along the right side of the cargo bay and before long you'll happen on a door. Go through to catch an announcement from Revas.
Now head out the door on the other side of this room. You'll exit to a drawbridge control. Activate that, then turn right at the other end and activate the crane from the terminal.
Take the ladder down from behind the terminal, then take the walkway around to the right. You can drop down onto the crane boom and cross to the floor below.
There are lots of drones ahead, and big gaps in the shadows. Watch for the first drone to turn its back on you (he's just ahead and making patrols around some crates), then book it up along the right side of the area. Hug the right wall to find shadows the fastest.
Let the drone pass you again and look ahead for a second one. When he's past, do the same thing and hug the right wall. You should be able to get out of sight pretty fast.
You can climb up over the crates here, but this is almost sure to get you spotted. If not, backtrack and stealth kill the two drones you passed and take the path into the center of the area through the crates, to the right.
Keep sticking to the shadows as you head along. You'll pass a few more drones, and there's another in the center section of the cargo bay that's raised up. That's where you're headed. Move to the right side of the room and find a crate to climb up to access the area.
Bounty! Bounty Card 34 is located against the back right corner of the cargo bay. If you're facing the back wall, head to that corner and you'll see it on the ground.
Climb up and wait for the drone to turn its back and head toward the center of the raised floor. Hug the back wall and move past it until you find a crate. Climb it quickly and duck into the vent there to end the mission.