Don't blink. Don't even blink. Blink and you're dead. They are fast, faster than you can believe.
Don't turn your back, don't look away, and don't blink!
Doctor Who Blink Part 3 - YouTube
For those who does not know what Weeping Angels are.
So. Is it possible to make make a script and use it on a statue that will follow a player ONLY when he's not looking at it (when his back is directed to statue 'eyes'), and when the statue catches him, he will take damage or simple die?