Harder but, I'm as insane as to say you could make it Even HARDER! Just add new kinds of guards every once in a while. Oh and new weapons would be nice to get. I also agree with wavehead and by new weapons I mean New close range weapons.
I had a high score, I had to go to the bathroom and I was like, Hey how do you pause? So i clicked main menu and guess what? MAIN MENU1 So I lost my 67 high score for survival, and I had full health...
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