There will be a new update in a short while.
What's New
1. Reduced occasional lags
2. Fixed a few cases where generals could be trapped by common zombies
3. Fixed a bug that objects of level 4-1 can't be finished
4. Fixed the error of duration of the Boss's stunning skill
5. Fixed the bug that text boxes could stuck on the screen
6. Optimized wording of difficulties. From "Regular" and "Difficult" to "Normal and Hard".