despite all of the comments saying the game is unbeatable, or to hard, i beat it on my first go.
firstly dont bother with the shotguns or smgs, what i did was fully upgrade the first pistol and use that, only going for headshots, till i could afford the second assault rifle. i fully upgraded that, and never needed to switch. the key is getting the long headshot chains. with the pistol you just need to not suck at aiming because it reloads so fast, the assault rifle however you need to make sure the last shot with the mag is a headshot, and that you get one right away after the reload.
my best is over 250 combo, best of luck and great time killing game
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