fitgirl has it. gameplay feels kinda dated, but with some nice additions. Looks pretty good, and the horde engine is cool, lots of baddies to shoot. Unless the pvp and online coop modes are amazing, I can't imagine it being worth 60$, but for the price of free, i'm digging it.
It is not, to the point i played there are 5 kinds of enemies:
Oh there was also Carnifex at one point but it was easier to fight than the warriors, but scripted so you couldn't defeat it.
I must admit all of those maybe except ranged warriors are very effective against my old and somewhat damaged nervous system.