Fun game, but a touch overrated in my opinion. Good skills and whatnot, but once I got my build squared away by the end of Area 2, it was mostly just fight, upgrade EQ, fight, grind if my level wasn't high enough, fight.
Just got the impossible badge!
Noble w/Bowgun(Impact,Leech,FireRate)
Rogue (sorta worthless actually, my mosquito killer)
Militia(Grav)
Ranger(Grav)
Bowmaster, Anti-Armor, and Active seemed to be the most valuable. I know by wave 60 that I would get the medal, and probably got about 50 perfects overall. It can be done, but you know pretty early.
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 "Sonny 2"){kind=icon}
 "Elona Shooter"){kind=icon}