Here are the power ups you can find throughout all the maps.
List of them all
NUKE
MAX AMMO
INSTA KILL
CARPENDER
DOUBLE POINTS
FIRE SALE
DEATH MACHINE
What they do?
NUKE: Kills all the zombies in your area
MAX AMMO: Fills up your amunition
INSTA KILL: Makes every bullet kill a zombie instantly
CARPENDER: Fixes all the barriers
DOUBLE POINTS: Doubles the amount of points you get
FIRE SALE: Puts the mystery box in every room for just 10 points
DEATH MACHINE: Gives you a mini gun (Map FIVE only)
WHAT THEY LOOK LIKE?------------------------ (all power ups have a green glow to them.)
NUKE: A big missile
MAX AMMO: A ammo box
INSTA KILL: A skull
CARPENDER: A hammer
FIRE SALE: A large tag
DEATH MACHINE: A bundle of bullets
HOW OFTEN YOU GET THEM?
NOT MUCH, MABYE EVERY 35 kills----------------------------------------------------------