Well this game looks a lot like old school Zombie Shooter : Left 4 Dead .
Ofcourse its not as good as L4D but its a decent game , it differs in :
you have 12 characters each with a unique ability and passive attribute
you build Card Decks to give urself and the team some buffs and sometimes debuffs
everymatch there will be random events that will indeed affect the total walkthrough , sometimes game will give u trauma that decreases ur max health , starvation event will drain your health as time passes unless you find food items and so many more events ...

weapons can have attachments and perks

with all these new features , I personally recommend L4D rather than back for blood

its not bad but its not worth $60 i didnt even get it for $60. If you really want to play it wait for a discount or go to CDKeys

hella good