Try a ranged character like the ranger.

Play on the beta branch under steam preferences. The boss is easier and less buggy. (it may be updated by the time you read this)

Get lots of defenses so you can make mistakes. HP, Armor, Healing.

When shopping don’t buy small gains unless they are cheap, stick to your plan. Rare weapons are the best value and power increase.

Focus on Luck early. Luck on turn 1-5 will make your run much stronger. I keep taking any luck I see until about floor 10 and then focus on weapons and defense.

Lifesteal is good with very fast weapons like SMG, Minigun, Flamethrower.
This is true to a lesser extent for AOE weapons but they often only hit 1-2 enemies.7. The more HP you have the better regeneration is. Regen scales based on your max hp.

Whatever items you have show up more often in the store. If you are holding a wrench, more wrenches will show up in your store. If you want more wrenches then hold 6 wrenches. Be careful not to hurt yourself by purchasing the wrong things.

Some weak stats:

• Range – slows down melee weapon attack speed, ranged weapons have plenty of range already.
  
  
• Harvesting – generally never worth it. If you take it on turn 1-3 it certainly pays for itself, but after that more DPS will earn you more credits and more luck you make your shop better.
  
  
• Engineering – not worth dabbling in. Don’t get tempted. You need to go all in or stay focused on your main build and survival.
  
  
• Elemental – super strong if you go all in, but don’t get distracted. If you find an early flamethrower on any char it is reasonable to swap to elemental build if it is early enough.

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