Awesome to hear!
I think there could be something there, I feel a temporary scare might not be too interesting. However, maybe you could have the ability to throw some kind of light or turn on lights that attract zombies away from you, just to play more into the idea of light and sound :)
I'm sure there's a cool way to incorporate scaring the zombies though, I'm just not too sure. Unless there was some kind of monster hierarchy and you you could use the head or blood of a monster they react in fear towards to spook them away :s Maybe there's something cool there
All depends on the implementation
Have fun experimenting :)
