Awful game, almost entirely luck based, sometimes games are impossible to beat, and advertising cluttering the screen at all times, along with pop-ups. Screw this, and how the hell did it get badges?
One minor complaint: please move the 'End Level' button to somewhere where it can't be clicked during gameplay. I was shooting the last few remaining zombies to the east so I could scout around for the ATM machines and hiding spots I missed but I ended the level accidentaly. Still a 9/10 game though.
Have you tried exploring the Grinnfinite Dungeon? There are reports that Rubies and other cool stuff can be found in there.