One word: Goregasmic
The content is 100% mature content with f-bombs every 2 seconds and some audio content that made even me blush when I had company over and I was playing it for the first time.
The game has great 70s style cinematics tracking the story line that resemble a Quentin Tarentino movie which I wish WAS a full length movie because it is HILARIOUS.
Game play is standard shooter like Link's Crossbow training with a consecutive hit bonus which ramps up throuogh levels like psychotic and hardcore until you reach "Goregasmic" which is timed by the second and tallied to your final score...which in the end contributes to $$$ for upgrades and extras like animation and music for the title screen.
Overall this game will blow you away like it did with me if a) you love B horror movies, b) love zombies (sorry Washington), c) love arcade shooters like Area 51, and d) love zombies.
If I wasn't a fan of the I would probally rate this at 7 or 7.5 and would recommend buying it used (bargain bin) cause it would get tired after beating the campaign of 8 or so levels.