So, the game kinda needs a system to pick up ammo and other weapons.. but other than that the one-shot kill is great! Really forces you to take cover until a window of opportunity arrives for you to shoot back! (Btw, make a main menu and have the level ACTUALLY restart)
Adding some new weapons wouldn't hurt either, maybe a few more assault rifles that are unlockable at levels 1 and 2 and some more explosives like C4 or an RPG.
A suggestion, adding some visual enhancement options instead of the "graphics quality" tab, would be a little bit better so players can adjust their visual settings to a full extent i.e. antialiasing, field of view, and qualities for.. let's say, textures! (Also, there is a music volume tab even though there is no music at all in this game!) XD
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 "Wargames first person shooter"){kind=icon}
 "Ballistic"){kind=icon}
 "Rush Team Free FPS Multiplayers"){kind=icon}