NOTE: YOU NEED EXTRA FREE RAM TO PLAY THIS GAME LAG-FREE THIS GAME IS NOT SUITABLE FOR LOW END DEVICES
Green Force: Zombies Udead is Back Again by Trinity Games with Partnership of Raptor Interactive
This is an ad-supported free version of the game.

Green Force: Zombies Undead provides a unique experience of FPS gaming and Zombies shooter without compromising on the subtle aspects of individual genres.
City is infected with deadly virus and people are turning into living dead causing mayhem. Government is trying to quarantine the infected areas, but failing completely. Those who survived the virus outbreak are at their own including the renowned professor Dr. Smith Kline. Who claims to have developed the drug to stop the outbreak and possibly cure the infected.
The Zombies are forced to live at the expense of non-infected and nothing but the flesh! It's only a matter of time that there's no survivor.
Green Force takes on the task to rescue the city and possibly save the world!
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The game offers story mode with missions of varying difficulty level. If you are only in the mood to kill zombies endlessly visit the maps in Survival or Turbo mode for some practice.
Survival and Turbo mode offer the selection of two maps you can practice in. Turbo mode is only different from Survival that the Zombies keep on respawning and you don't have the time!
You have the choice of different weapons. Visit the armory section to select the Primary and Secondary weapon combo. If you run out of ammo in one of your weapon just swipe on the weapon icon to switch.
Remember the world is counting on you and you need to survive through the missions and manage your ammo carefully.
Good luck commander!

Suggestions and feedback always welcome.