This mission takes place in the Sanctuary Hole after the mission Bright Lights, Flying City. Visit Marcus after you return to Sanctuary and he will tell you that his most precious chest had fallen from the city when it lifted off. He will then ask you to return to the Hole and find it. Make sure you talk to Sir Hammerlock and pick up the mission "Perfectly Peaceful" from him.
- XP: 2333
- Money: $492
- Gear: Choice of Shotgun or Relic
Head down to Three Horns - Divide and head to where Sanctuary used to be. When you get there, you'll see the destruction left behind when the city flew into the air. Go through the front gate, up the stairs and turn left. Almost immediately you'll be attacked by Bandits.
If you stay where you are, you can draw the various bandits down this long hallway to make them easy pickings. The first few enemies will be Psychos. Not long after them will be a Nomad and well behind him will be a Goliath. Use fire weapons and you should make quick work of them.
Go through this next room at the corner (you just killed the enemies from it) and up the stairs into the next building. You'll hear somebody talking about dropping something. Continue up the stairs to the top and you'll encounter more bandits. The first one you will notice is likely going to be a Badass Goliath. Behind the Goliath will be Midgets, Psychos, Suicide Psychos and Burning Psychos. To the left and around the corner will be a Nomad or two. Try to hang back by the stairs for as long as possible. You can always head down the stairs for cover if you need to.
After you've gone through them, go up to the next platform and you should see only a couple of enemies there. In the distance is a slag barrel that you can use. Get under the red tent ahead and assess what enemies remain. From here, they can only approach the way that you got here. If there are Psychos, wait for them to come up the stairs and finish them off. Clean up any other bandits that may be around and then travel forward.
You'll come to a set of stairs that will lead down to a checkpoint. There will be another set of stairs that lead further down. At the lowest point, open the crate for ammo and then head back up. Before going up the stairs to the check point, stand just left of the stairs and jump over the railing.
You'll land on a large warehouse like building below. From here, you can fall off of the roof and make your way to the lower levels. You can actually pass right by this building to the lowest level and enter into the Caustic Caverns if you like however, you'll probably want to find a way into the building to kill the bandits inside and finish the bonus objective. Be careful because there will be a Caustic Goliath here and if you remove his helmet, he will spew acid everywhere.
After you've killed them, head down into the Caustic Caverns by going to the lowest point.
There are several other missions you can take while in the Caustic Caverns including, "Perfectly Peaceful," and "Minecart Mischief". Just inside the Caverns, stock up on ammo and sell any extra loot that you don't need. There will be a set of large doors to the North and to one side of them will be a valve to open the door. When opening chests and crates in the Caustic Caverns, watch out for Varkid Larvae popping out.
Go through the door and you'll come to a construction site with bunches of small Varkid. It's far easier to run right past them than to kill them since they are so small. Immediately head to the right past the giant yellow truck and follow this path. It will take you through a cave and right up to the walls of some kind of installation but you don't want to go that way. Take a right and you'll see a large pool of acid and a few islands that you can hop across.
Make your way across the stepping stone to the larger island in the distance. When you get to the far side, you're going to have to fight your way through some Volatile Crystalisks. They can really take a beating and if you let them get together, they can be veryh difficult to kill. Because of their slow speed, you may just want to run right by them.
Follow the island south a little ways until you see a ramp that curves back and up into a cave. Go through the cave and you'll come out to the far side of the island. If you look closely at the structure in front of you, you may deduce what's about to happen.
Approach the large round structure with the chest on it and then back away when it reacts. If you've been able to handle the Crystalisks before with decent success, Blue shouldn't be too tough. Like any other Crystalisk, go for the crystal feet. He will use ranged attacks like normal but you should also watch out for the baby crystalisks that will appear. When you've destroyed the front two feet, you'll have to make your way to the back. Since he's so large, it may be easier for you to go through his legs rather than past the sides and risk the acid pools.
When you've killed Blue, he will sink down and you'll be able to grab the chest. Take the contents back to Sanctuary and give them to either Marcus or Moxxi for a reward.