this game is great. 5/5. for the sequel, if there is one, developers - please take this piece of constructive criticism into account. change the difficulty curve, as many people have been complaining about. it seems as if after just a level, the curve multiplies tenfold, and I am not able to win. also, online play would be amazing - I'm sure many people would continue playing, as the mechanics of the game are solid. movement, controls, firing, everything. great game, just need to fix some minor issues. any other gamers reading this comment, if you agree, copy and post to keep it alive. the developers should see this - making a great game even better is what we all want.
found a glitch :D Use something with a grenade for secondary attack (spacebar) then shoot all of your grenades then once your out shoot an entire clip of your weapon. Then if your grenades say 'Na' then you did it right and you have unlimited nades for your gun! Enjoy.