Angry Granny vs Zombies

Fending off the odds of the world to save the old car dump, our guardian granny had been keeping everything in place for more than two decades.
A shrine for the little group of small-town kids to play football, and old grannies like her to come and have some chat. The car dump was not the usual forlorn forsaken by the world, it was a small world in its own.
The guardian granny was very adept in weaponry and even set up a small mechanic shop to teach the town kids to repair car parts, teaching them the art of restoring antiques and fixing the newer models of cars to earn a decent living. That was however the one side of the granny, the soft one but if someone went against the rules of car dump, she would be crazy with anger. Her anger was the only thing that everyone around in the community was afraid of.
Everything was calm and peaceful, then one day everything went silent, not even the birds were cawing. Only the cranky sound of old rusted iron in the car dump and the thump of granny’s walking stick as she surveyed the surroundings. Apocalypse! Apocalypse! Someone was crying out loud and then there was a crunching sound of tearing apart of flesh and the lousy walking with drooling echoes. Zombies! The granny thought with a startle. She had heard about zombies but never took them seriously, more like folklore than a reality… and that reality was here in the form of the zombie apocalypse.
She hurriedly turned on the current in the electric wire fencing of the car dump. She was the fiercest of guardians when it came to protecting something, and so she did. She prepared the rifles she had in store, years of experience with taking shooting as a hobby will now help her save herself and her precious car dump from the zombie attack.
As the night fell, granny noticed a troop of senseless zombies with drool and decay all about advancing towards her car dump, leaving gore around. Not only that, but there were also zombie robots too, eating her cars. She became very angry seeing this and started shooting at them straight. Spilling green zombie blood everywhere. The granny is not giving up her ground that easily, and she is going to fight against the zombies till the last bullet. She is the one-man army against 20 zombies and zombie robots. Help the granny through 30 levels on an intense counterattack, with 10 model guns, 3 different places, and much more.