It got more interesting as it went along. What confused me is how I was able to jump on the enemy's heads. I thought you could only shoot them at first. That was kind of a rude awakening. The animation could have been better. I still like the upgrades.
I like their screams when they die. There's just too many of them. It was easier to just jump on them. The music was pretty good. It did get distracting.