Very simple but addictive. Some items are more overpowered then others but with the kind of game this is and how many weapons you can have at once I don't really have an issue with that.

I've reached the ending added in 1.0. After getting to that point I'm more appreciative of how the simple gameplay loop did not get old to me after over 20 hours which was one of my worries about the game. In fact there's so many unlockables I can still find I have plenty more reason to put dozens of more hours in.