A good game with a structural flaw..
This game is really good.
I ALWAYS loved the pixelated style, alongside the lots of blood and the bazookas. But, it's repetitive. I say, this got boring after the 11st wave.
It's repetitive, and some weapons (the grenades and the bishot gun) makes everything boring.
I liked the upgrade system, but it would have been better if you would have added the possibility to buy health and to repair the tree.
Oh, yes, the plot is really good and original.