|Metal Shards, Metal Vessel, Sparker, Wire, Machine Core - Medium, Luminous Braiding, Shell-Walker Lens, Shell-Walker Heart|
Cauldron RHO Override. Shell-Walkers resemble crabs and they carry large crates on their backs. These crates can be shot off by hitting the supports on the back of the machines, and they can be looted independently of the actual Shell-Walker. If you hit the supports to knock off the crate, then they can scramble to reattach it by using their Lightning Gun arm. Destroy this and the crate will remain on the ground indefinitely.
Speaking of the Lightning Gun, it can use this in combat to either fire off a volley of three smaller shots or one bigger shot. The other arm of the Shell-Walker has a shield, which it will erect all the time when it's in active combat. Of course, this can easily be shot through and taken out temporarily with enough damage, like a precision arrow. It can lunge at you with its claws, sometimes in quick succession, as well as release an electric shockwave if you're close enough.
Combat with the Shell-Walker isn't too bad, but you might want to equip an armor with some shock resistance. There is a Power Generator on its stomach area, which is a little hard to hit (could try laying down some Blast Wires), but it disables the Lightning Gun, Shield Claw and deals shock damage to the machine. Thankfully, the Shell-Walker is a bit slow, so getting around it and all of that is fairly simple. Get rid of its main offensive and defensive weapons, and the Shell-Walker is yours.