Several games fit the "Kill Zombie" description. Here are the most common ones users look to "hack" for extra resources:
Searching for a "Hack" or "Mod APK" for a game titled (Kill Zombie) usually refers to modified versions that offer unlimited resources or unlocked features. Based on popular titles matching this description, Popular Games Matching Your Search
: Go to Settings > Security (or Apps ) and toggle on "Install from Unknown Sources" so your phone accepts files outside the Google Play Store.