To beat the last boss, spam the second last level until you and the crew are maxed in all skills. Then during the fight, you always focus on the boss, shoot him almost at all times. The only time you do not shoot him is when you have to kill the totems spawning zombies ASAP. Focusing the zombies wastes too much time in the level, leave them to your team. You can thin out the waves a little but primarily you should focus on the main boss when there are less than 10 zombies on the field .
to get that medium badge and the 3 minutes achievement its easy! Just start a new game, open a new tab browse facebook or youtube for 3 minutes. then return back and see a new highscore
Listen Up!!
One of the best pieces of advice for the hard badge is the just stay on the edge of the circumference of the screen and just keep looping rings of the rectangle until only a few enemies are left. Then take them down as standard. The bullets are destroyed If they hit the edge so staying close to it makes you near invincible except for the rare stray bullet
This game was the worst, game on this site that has badges. It is completely glitchy and certainly didn't deserve any of those hard or impossible badges
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