Play sound when looking at enemy?

Not a good question.

: http://answers.unity3d.com/questions/133869/how-to-ask-a-good-question.html

: http://answers.unity3d.com/page/faq.html

Why don't you just search Slender on this 'site. There have been alot of these questions since that game (and I thought it was Dr Who and the Weeping Angels that started these questions!)

http://lmgtfy.com/?q=how+to+play+a+sound+in+unity

http://lmgtfy.com/?q=how+to+cast+a+ray+in+unity

more then you deserve for such a question.

Just so it cannot be said that I wasn't constructive or helpful :

http://answers.unity3d.com/questions/287355/slender-like-game.html

http://answers.unity3d.com/questions/296068/how-to-make-a-slender-man-follow-character-script.html

http://forum.unity3d.com/threads/134862-Slender-Man-Design-Outline

http://forum.unity3d.com/threads/141488-Slender-Beta-0.9

http://forum.unity3d.com/threads/138399-Slender-Man-WIP

It's up to you to find the useful information among that. Read.

Break it down to one simple thing. Work out how to find if one object can "see" another. Once you do that, you can make it do anything you like with that as a trigger. And you can do it both for the player and the 'man' .