Go through and follow the path. Through the door on the other side, you'll soon exit back outside. As you do, look to the right for three enemies to kill.
Don't go too far out of cover as you deal with or finish these first three fighters -- there are more mercs to the left, across the water on different walkways. You'll want to mop them up, too.
Grab some new weapons off the bodies, then use the SCAR gun to shoot the flashing button the far side of the walkways. It'll extend the bridge.
Cross the bridge and run straight, then go through the door to avoid rocket fire from the Alpha Drone across from you.
Bounty! Blast the wooden doors to get out of this shack and follow the pier out to the corner near some crates. You'll find Bounty Card 48 there.
Backtrack back to the videolink and prepare to head back outside the way you came.
Bounty! Check this room for a ledge you can climb up to, into an attic. Inside is Bounty Card 20.
Sprint back across the bridge to the right and blow open the wooden door there. A nanomed machine is inside.
Take the stairs to the right all the way up. You'll see a spider turret appear at the top. Blast it, then open the wood door beyond and continue.
This tunnel affords a decent place to engage that big Alpha from. Wait till it opens fire on the tunnel and the light will get knocked out. Make it lose track of you, then use the shadows to get close and put four rounds into it. Explode them and go in for the kill.
Take the drone's grenade and toss it at the nearby shanty on the wall. You'll know it from the explosive tanks inside.
Bounty! Inside that shanty thing is Bounty Card 27 and a nanomed cartridge.
Bounty! After killing the Alpha, go down the stairs at the front of its area. You'll find a vent. Take the first right turn inside to find Bounty Card 18.
Head to the right side of the back wall of this area for a place you can climb up to advance. To the left you'll find a ladder to descend. At the end of a hallway at the bottom, shoot the wood cover over another ladder and climb down.
Mercs have set up an ambush for you ahead. Pull out a more reliable weapon than the SCAR, like an assault rifle or shotgun and prepare for a fight.
An effective strategy is to take out your shotgun, fire a round to draw out the mercs, and step back around the corner toward the ladder. The poorly programmed mercs will pile up at the corner, allowing you to decimate them at close range. When they're down, head for the elevator shaft and look up.
Equip the SCAR gun. The elevator has four breaks. Plant a SCAR round beside each one and detonate them together to lower the elevator and board it. Then proceed back outside.
Bounty! Go straight from the door to a small area you can drop into. At the mouth of the vent there is Bounty Card 50.
You don't need to follow the vent. Climb back out and follow the path outside.
Bounty! From Bounty Card 50, look up for a walkway above you. Climb the nearby crates and jump up to the walkway. Follow it to Bounty Card 17 to the right.
On the left here is a wooden door, and inside a nanomed machine. Continue along until you come to another wooden door at the far end of the area. Open it and hit the button inside.
Go to the newly opened door. You'll have to take out two drones, who come running out as you approach. Continue through into the arena.
Inside, you'll get flak from some mercs. Look for drones on the upper level to pop. Kill them, then get out a strong gun like the assault rifle. Drones will be dispatched into the room -- first one at a time, then in a team of three.
Kill those and the mercs will send in an Alpha. Strafe around the center platform to lose the Alpha, all the while plugging it with SCAR rounds. When you hit four, blow them and finish him.
Climb onto the platform and look up for a button. Hit it with the SCAR gun to raise the elevator.
Turn right and look for a ladder. Climb down, hit the door button, then exit to the right back into the arena. Jump down and exit by the new door.
An Alpha is stationed to your left, opening fire on you. You need to run along the path to the right to avoid it. As you go, kill the spider that appears in front of you and bust down the two wooden doorways.
Bounty! Exit the second wooden door. You're standing where the Alpha Drone just was. Look left for a spot where you can drop down and find Bounty Card 38.
Turn back and head in the other direction. You'll fight the Alpha. Repeat the usual strategy to kill it.
Bounty! To the right of this area is a chainlink fence covering a room. Throw an Alpha grenade at it to open the way and find Bounty Card 44 and a cache of weapons.
Head back through the door marked "Stand Clear" to enter the refinery. Inside, follow the path to an elevator and take it up. At the top, hug the left wall and make your way to the shadows. The red laser sweeping over the area from the left side of the room is an indicator of a spider turret. Blast it.
Shoot one of the crates nearby over toward the wall with the turret, then use it to climb up. At the top, you can use the nanomed machine, then make your way left. Use the hangrail there.
There are mercs patrolling down to the left. Drop off the hangrail and hide in the shadows. If you can take one or two out with the SCAR without being seen, do so. Then drop down.
When you've cleared the room, press the console and find a place to hide, preferably to the right of the room. A group of three mercs will come police the area. Take them out and use the door they opened.
The room is about to fill with a few drones, so find a place to hide off to one side and take them out.
Bounty! When the drones are gone, use the SCAR gun to push a crate to climb the structure that's to the left of where you came in. Climb up to find a conveyor belt that's switched off, and Bounty Card 25 at the far end.
Head down the ramp to the left. Look up to see a spider that would have attacked you from behind.
There are actually spiders all over this room. Trace the red lasers back to their sources to find the turrets and destroy them. Go slow and sweep both the left and right sides as a few are pretty distant. Also look for drones up on the higher levels, above the area you're entering. They're to the right.
Check to the left of the base of the ramp for a nanomed machine when you're done with the shooting.
Bounty! From the nanomed, look for a ladder near it on the wall. You'll climb up onto a catwalk above some large vats. Follow it to the second vat, where you'll find Bounty Card 55.
Head back down and advance to the right. Go down and then turn right again for another doorway. At the end of this hall are spider turrets, including one directly to the left that will destroy you if you're not careful. The others are above to the right and above out in front of you.
Bounty! Walk straight out toward that big round tank. Go around it on the left side to find Bounty Card 51. Watch out for a drone attacking you from behind when you grab it.
Turn left and go up the ramp. There are two drones up here, plus spider turrets on the wall to the right and down the hall to the left.
Bounty! Go to the right at the top of the ramp and head around the side of the wall. Around the corner is a long corridor. Follow it down, kill the turret on the wall ahead, and look a little left for Bounty Card 36.
Back at the ramp, turn left and follow the hallway. You'll see a merc in the next room with his back to you. Take him out.
Bounty! In this room, go to the far right from the hallway where you enter. Along the wall there, you'll see a big cable/pipe you can jump down onto. Walk along it to the end to find Bounty Card 56. Then return to where you started.
Climb the ladder of one of the nearby towers. Follow the walkway to a console and hit it. Two mercs will appear in the area behind you. Shoot them from afar, then doubleback the way you came.
Another merc is waiting for you in the next room. Kill him and turn left, where two spider turrets guard the door forward. They're on either side of the door.