I was playing Terraria earlier, having just reached the Hell layer (~3000ft.) and after I killed one of those annoying imps, I got a message stating:
You feel an evil presence is watching you.
I read on the official Terraria Online forums that it means the Eye of Cthulhu is about to spawn at the surface. Unfortunately, after receiving the message, I saved the game and quit to look online for that message means (while still in Hell). When I reloaded the game and spawned at the surface, during night-time, Cthulhu wasn't there.
Is there any way to get the Eye back?