I'm creating my game, Psi, with a beat-em-up style layout. What would be the easiest way to make a knock back effect to drive the zombies backwards from the player when they're hit, whichever way the player is facing? Here's a picture to give an idea of the layout:
<img src="https://dl.dropboxusercontent.com/u/60595907/Screenshot%202014-01-18%2016.05.53.png" border="0" />