Borderlands 2 Walkthrough Part 62 – Caustic Caverns Sidequests: Perfectly Peaceful

Pick up Origin Evidence: 4
Head into the Caustic Cavern through the bottom of the Sanctuary Hole. Once inside you will need to find 4 recordings from the head of Security of the mining operations inside the Caverns.

ECHO Record 1
Just head forward through the first area of the Cavern. You will find it on the right on a pile of Garbage.

ECHO Record 2
Head to the Northeast from the first recording. Proceed through Oozing Discharge, going through the cave and past the Threshers.  When you start to encounter those, turn to the East. There is no shortage of them. When you cross into the Infested Warehouse be wary of all the Varkids. Still, kill them all then head for the middle pillar. There you will find the second recording.

ECHO Record 3
Head to the West through the Infested Warehouse into the next area and press on toward the next recording. Head to the North after you have dealt with the Varkids in the Warehouse. When you make it the Guardian Ruins start over to the West and look for a sharp drop to a lower area.

ECHO Record 4
Head all the way over to the East then turn to the South to start toward this final recording. Head the slope past the Guardian Ruins and follow the mine cart track into the old Dahl encampment. Head though the airlocks to the second. Turn to the South and head through the Nether Hive, bearing to the Southeast. When you reach the wall look for the door. You will easily find your way through to Dahl Core 06 from there. Just head into the top-right corner of the room to collect the final ECHO Recorder.

Kill Spiderants: 10
You can find plenty out in the Dust behind Ellie's Garage. Aside from that, in the Caustic Cavern you can head to the Nether Nest and there are plenty there you be killed. You will find it to the Southeast of the Abandoned Mining Camp through the second airlock along the mine cart track.

Kill Threshers: 5
Head to Lake Shiny Horizon in the Highlands or underneath the Blake Bridge. You will find no shortage of threshers trying to kill you. You will also find them in the Northeastern area of Oozing Discharge. There is no shortage and you will easily hit the 5 needed.

Kill Crystalisks: 5
This is easiest to do inside the Caustic Caverns as they are everywhere. Remember to charge up to them and melee their legs to keep life simple. Once you remove the crystalline structure from its 3 legs be sure to move back as it will then explode.

Rewards: 3859 XP, 4 Eridium