This is just Space Invaders with no walls. -.-
Rather simple but the menu options, having to click twice to continue, once for score submission then again in a specific area, is just a bit annoying. A nitpick.
It's "Kill", or "Cull" if you're weird, but not "Kell".
That's right; resident grammar Nazi here to smack you down. Jokes aside, your game is boring. Nothing technically wrong with it, I suppose, but it's a poor copy of a tired genre. Add something new! Be bizarre! Don't just make a weak copy of that game you played last week.
Good game i kinda wish it had some sort of upgrade system or if the bad guys dropped some kind of boosts but other than that i give it a 3.5/4
Concept isn't all that original, but it's well executed... Nice graphics; they have a clean, crisp feel to them.