Good simple game.
The only reason why people are complaining is they are expecting something along the lines of one man mowing down thousands of zombies to protect his family.
Very simplistic which isn't always a bad thing upgrades would be nice though the speed increase makes it better than some other games with no change what so ever.

This game is fun & challenging! As the levels rise good luck playing without a mouse heh heh.
I would love to see 'Protector 2' have a $ and upgrade system. that would make the game awesome!!!

Okay, just as everyone else says, this game is very basic and there is not much to it. However, I do not find this to be much of a problem to be honest. I still find the game very fun and addictive. It is simple, but this makes it very straight-foreward and a good test of player endurance as well as reaction time in the later levels of the game. The game does not pretend to be like shooters or anything and it is this simple type of gameplay that I have not seen in a long time that attracted me to it and kept me playing. It also has an excellently executed speed increase curve on the zombies as they race down the screen, this makes the game flow very well from one level to the next. IMHO.

Just two lame, at least add a saw upgrade, or some kind of bonus zombie that will make it bigger for a little. You could add stronger enemies so forth.

Basic game, first at best.