Okay, I used 1 hour on these scores:
The badge, level 57, 8443 zombies killed, around 660000000 points, 999x multiplier, 73 consecutive kills, my method? I got to level 25, used my rocket luncher, with rapid fire and just shot up and down, collected some ammo boxes and you just continue to do the same thing, over and over and over and over...... Awesome game, 5/5!
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