If you have Doctor’s Order open and preferably active (with ideally 0 Notes collected), you could farm the 4 small cardboard boxes in the room with the Red Chest (near where you look for Bloodwing) for LLMs in WEP. If you have Rocko’s Modern Strife open (don’t speak to Rocko), you could farm the various containers in Thousand Cuts for LLMs without worrying about being attacked that much since enemy spawns are greatly reduced while the mission is active.
You should also consider farming Knuckledragger for a decent Hornet (Corrosive) Pistol. For most characters and builds, the Hornet (Corrosive) pistol is the best Corrosive pistol to use. It will help out with the Surveyors and Loaders at the Peak. You also might want to farm Frostburn Canyon and Ellie’s Garage (in the Dust) for Tubby enemies. They can drop some of the Legendary COMs, in addition to some Pearlescents and other things. If you have the How Marcus Saved Mercenary Day Headhunter Pack, you should spend some time farming the Loot Train for Legendary or Pearlescent items. For Zero, I would recommend getting a good Pimpernel and / or Lyuda Sniper Rifle.
I also recommend consulting the following:
The Community Zer0 Guide - All you ever wanted to know
Resources of the Mecromancer Variety
They have very useful info on Skills, Builds, Gear, etc. for those characters. Good luck!
Forum ID: Poisd2Strike
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Gun Prefixes | Gun Parts | Max Stats
Maya OP8 | Banshee RR / NRR | Binder | Cat | Nurse | Siren | Trickster B / M