Chillingo's top-down shooter Extraction: Project Outbreak can now be liberated from the confines of the App Store and added to your iPhone for free.
This affectionate homage to old skool titles like Cannon Fodder might look like yet another zombie blast-'em-up, but its varied weapon set and clever firing mechanic have won over critics and fans alike.
Cast as a private military contractor, you must clear an exclusion zone that has been locked down following a viral outbreak.
The symptoms of this virus will be familiar to any George Romero or Resident Evil fan: an awkward gait, constant moaning, and a lust for human flesh.
You guessed it, folks: those irresponsible military scientists have accidently created another batch of zombified mutants, and it's up to you to dispatch them using whatever hardware you have handy.
Speaking of hardware, your available arsenal gradually expands beyond pistols and machine guns to combat drones, and even helicopters, making mowing down your braindead foes a visceral treat.
If you want to join the fight, head on over to the App Store and grab Extraction: Project Outbreak for your iPhone for absolutely nothing today.
View the Extraction: Project Outbreak video below...