good game; still don't get the order you fill the vials? yeah they are in the picture seems you just randomly fill them in... that's what the walkthrough does...
impossible badge complete :) for the swordsman hit him with a regular attack when he is at range max. otherwise constantly move away. if he is too close for you to hit at range max inch closer till he attcks and hope that he does one of the attacks that makes him move farther away.
get militia companions with rocket launchers or grenade launchers and mod them with auto reload.
if 1000/fire rate > reload time (ms) then they basically never have to reload. currently able to beat levels without even firing my own gun, wave 41.
such an easy hard badge, just go around the edge of the map in a circle lol. they shoulda made this game with no edges now that would be intense only thing that would save you is lag :D