Interdimensional Traveler

You decide to keep moving. As you walk you notice piranhas jumping out of the stream. Boy are you glad you didn't go in there!

After a mile or two, you see what appears to be a well-fortified castle. You wonder what this is all about, as you walk closer to investigate.

Then you feel a sting in your neck...You happen to notice the dart sticking out of your neck just before you pass out...