Nothing new duel stick shooter that is fun none the less.
There's a lot of fun to be had here, you basically just keep killing zombies, of course there are different types of zombies, from you're basic shuffler, to zombies that throw knives, run at you with explosives, or shot at you, etc.
You progress through levels, but the game saves after each level, so once you beat a level you've freed it up to continue at any time. This was great as I didn't feel like beating all 50 levels in one sitting.
There are also different modes in the game, an online multi-player as well.
It's mindless fun, adds nothing new, offers little story, and once you've beaten it and gotten all the achievments like I did, you can't think of a reason to play it again. But at 800msp it's worth playing for a diversion.