Preparation

- Pick Nox and level her until she have all passive slots. You want +HP, +AP, AP economy and most important, being able to upgrade your starting gun and "normal bullet bonus are doubled". Sadly, there is quite a bit of grinding before your character turn viable.

- Keep any "rifle" (3 bullet icon) weapon and any normal" type of weapon (single yellow bullet icon). Some weapons like the K-1 and Heavy Machine Gun have both. Your goal is to have the +5 (+10 with passive) bonus that will make some weapons insanely strong, including your starter gun. Normal > Rifle if you need to pick one. You need 7 "normal" and 6 "rifles" and Its possible to get the full bonus on both with just 8 weapons.

- When you are low level, it's ok to use whatever you get and some weapons like Edson are good room cleaners, but as you progress it's simpler to just focus on your pimped up basic gun, a spare for bosses and cash in the pocket instead of relying on a weapon that will break in the middle of a fight.

- There are TONS of terrible weapons in the game.

Money

- Sell any weapon that are not the ones I mentioned. You want to have cash in hand if a vendor appear.

- Eventually, as your progress in rank, your starting weapon turns into a S-tier weapon and you think this is great but this also means upgrading it cost a lot. Only upgrade it if you have money to spare.

- Always buy the artifact (last item) in the shop. You want to make the pool smaller to raise the chance of good items appearing on NPCs or chests. Buy even if it sucks otherwise it may appear again.

- Also buy any weapon that will help you fill your rifle / normal combo. They are usually B-grade weapons that are cheap.

- Always try to have roughly 500 cash in hand to be able to buy an S-tier artifact / pet.

Mechanics

- Because of the durability thing, its usually better to focus on making your basic weapon as good as possible since it doesn't break. I use the basic weapon for everything and sometimes have a "special" weapon just for the boss. Some good boss weapons are the Drill Sergent, Heavy Machine Gun and some S-tier shotguns, assuming you have the full normal bullet bonus.

- Burn, slow and freeze doesn't seen to work on bosses so any special effect that need those to proc won't activate either.

- Some weapons can penetrate solid ground / shields, but it's usually not worth the trouble of keeping them just for that factor alone.

Personal Opinions

- Crusader Armor (50% dmg reduction + 80 HP) is the best artifact in the game

- Heavy Machine Gun is my favorite weapon.

- Given a choice, always go for +HP and +Dmg.

- It's ok to keep +melee weapons (sword icon) for the dmg reduction. I usually sell it all tho to keep it simple. Most bonuses are, imo, trash.