reinbough is pretty hard you need to specialize. I beat it with each player retreating war machines one space. Southwest player built air + anti-air, middle player built heavy tanks and north east player built infantry with an anti air and one heavy tank. Takes a long time.
Logged on and instant hard badge :P, too bad I keep dying on floor 7 of a hero is born since my party keeps dying. If you need help check the wiki, it's amazing.
to get 5,000.
Make rounds last the longest and scale up slowly. Use the harpoon to get a bunch of pincussion bonuses and headshots. After getting the first one or two combo bonuses for pincussion, switch to gibbing. After first gib, switch to dart grenades, sit in a corner and put a dart in someone's head. Jump in the air and all the bad guys will clump and jump together, the dart will give you multiple midair headshots with double and triple kills to finish off, got 6300 that way.