If the game freezes, just click inside it (games can get unresponsive if you click elsewhere on the page).
The player must survive from zombies attack within a certain time. There are 10 kinds of weapons, 9 kinds of zombies and 5 kinds of battle areas in this game. If a player dies before time runs out then the game is finished.
AD to move.
Use mouse to aim and shoot.
!-5 to change weapon.