I really liked this game and found a pretty solid strategy throughout. Try to complete a "10" starting in the corners and work your way from the outside. Hope that helps.
I just couldn't get into it. As much as I wanted the medium badge, I just couldn't keep going. Upgrades don't seem to help enough to make up for the gold grind which makes it feel like it's just not rewarding enough.
I had originally given the game a 3/5 for unbelievably dumb AI, near impossible one-hit-fail quests, and pitiful quest rewards. But I think the difference between mission 14 and mission 15 is so absolutely absurd, that I have to give the game a 2/5.
This game was really boring.. just upgrade your starting pistol and that will carry you all the way through the game. The enemies move really slow so you normally have no more than 2 enemies on the screen at once. I just didn't find any challenge and the pace was painfully slow.
Tried getting hard badge with Hashcat's method and found that there weren't enough objects to collect. 81% of objects, avoided all reds, and still managed only 3.5million. I went with Abstract, Radar, and breathe, and got over 6.5million, only collected about 35% of objects, and hit about 3-4reds.
 "Trollface Launch"){kind=icon}
 "10"){kind=icon}
 "Battalion Commander"){kind=icon}
 "10 More Bullets"){kind=icon}
 "Achievement Unlocked 3"){kind=icon}
 "Robot Wants Puppy"){kind=icon}
 "Mighty Knight"){kind=icon}
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 "Dirty Earthlings"){kind=icon}
 "Kitt's Kingdom"){kind=icon}
 "Super Villainy"){kind=icon}
 "Last Robot 2"){kind=icon}
 "Bearbarians"){kind=icon}
 "I Love Traffic"){kind=icon}
 "Protector"){kind=icon}
 "Ultimate Monster Mayhem"){kind=icon}
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 "Music Catch 2"){kind=icon}
 "Band Of Heroes"){kind=icon}