I have a yellow lab who-like most of his kind- loves to swim.
He is my angel, I am very emotionally attached!
In the dream, I was on top of a cliff overlooking a large lake. My friends were camping to the side of the lake, and I could see them from my position, but they were very small and hard to make out. My dog, also very samll, jumped in the lake and began to swim out to the middle towards a duck. I felt worried for him because it was such a big lake and I thought he might not be able to make it all the way out and back, and I was not close enough to 'rescue' him if need be.
When he got out to the duck, he dove underwater and I couldn't see him at all. I started to jump around and wave my hands to try to get the attention of my friends, but they didn't see me.
So I jumped.
Instead of being in the water, I was now standing on the side of the lake, and saw my dog swimming toward me with the poor duck in his mouth.
All of a sudden, an enormous creature emerged from under him- my dog was the size of an ant next to this thing. I never really saw it clearly, it was just a huge mass of black sludge, and I knew that it wanted to eat my dog!
I knew that I could never take on this beast, so my best bet was to use myself as bait to distract him from my dog.
I ran along the side of the lake, sreaming and jumping and making as much commotion as I could, and the beast came at me.
The movement created a wave which swept my dog to shore, and to safety.
I grabbed him (and the duck, which was alive) and we ran away, while the lake monster made all kinds of angry noises at our escape, and then sank back into the water.
The lake was placid and serene again.