Notes from author
Using my default build and just changing the equipment. I've found this build to be very helpful in dealing with the Bed of Chaos. The Long Bow and Firebombs are all you need to take on this boss, but the rest of the equipment is used for the case that you get one barrier and are still trying to get the other by aiming at the right angle. The Black Iron set provides some good physical defense (in the case that you get hit) but by the second phase, the Bed of Chaos will be coughing up some fire at you from the center (the place you want to firebomb from). The Black Iron set provides some good flame resistance, but using the Flame Stoneplate Ring and Flash Sweat should help out a lot as you're struggling to get back up and aim at the second barrier.