All the challenge goes away after the 30th floor. Money no longer is a problem, and gear gets immensely overpowered for there to be any luck or planning involved.
I found the most effective way is to be a rouge and try to get the revolver as early as you can. Then upgrade it's fire rate by 2 and then reload rate. Take care of ground enemies, revolver even works good on armored, while your partners watch both air and foreground.
COPY WITH YOUR NAME AT THE BOTTOM IF YOU THINK THIS DESERVES BADGES!! Nabillionare, Kanara_96 brockey ,hallaluya ,Dr3tch ,mastermax, Gord163 , James865218,Razon,meanoo555, guerosinfe, Dofoid, sylver3000, Sahiro, DawnofShadows, oFridgieo, JeffHardy9, hyperferretlolz, lazercollab, muto_kazuki,chickenmanrlz, 9skillled9 Jamiefun4,linkshimers,Dragonxoxo, xweet14,RazorRaptor9, Tracer42, Fallingflamez,linkshimers,chickenman,Ruton101
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