GREAT GAME!
the first game looks like target practice compared to this one... (or maybe I'm exagerating (sp?))
[although, for some reason, I'm on level 14 on easy... I don't hear any music and there's just a grey background... is easy supposed to be endless?]
couple notes for the guys having trouble beating this game: level 10 shockwave does wonders. it will kill the strong red stickmen (the weak ones have 9 HP), and you get it every 15 seconds or so. upgrade to it ASAP, and then upgrade the guns!