What the f@$%!!!!

Something that appeared to be a Golden Retriever ran past me today.
It was huge.
So huge that when it ran it sounded like a horse was galloping when it was approaching
and
I thought,
"Why am a hearing the sound of hooves hitting pavement? This is not that kind of neighborhood..."

It was then that the horse-sized Golden Retriever ran past me.

My theory is that someone was walking it, then got eaten by it causing it to grow to it's freakish side. Then somehow it grew horse hooves and thought,
"I'm just going to run past people all day and scare the shit out of them! That's what I'm going to do for the rest of my life! Me and my new horse hooves against the world!".

That's the only explanation I can come up with.