Earth bound, I'd say El Chupacabra that's my pick. It seems to be some kind of mutant/hybrid wild dog.

Extra terrestrial beings (Space aliens) would not surprise me, but we will never get to meet them, unless multi warp speed travel becomes a reality, for us or them, or we find that worm holes do exist and we find one relatively close by that just happens to end up next to another inhabited planet. And we find someone with balls enough to enter the worm hole.

CFH, what does FTW mean?