A combination of all of those. But if I had to choose one, I'd say Godzilla.

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"Duty is the most sublime word in our language. You cannot do more. You should never wish to do less." - Robert E. Lee

Zombies most likely, for some actually have seen zombies. There was like around 10 Crypts (for those who don't know it was a infamous gang) was sited crowded around 3 people who looked bloody and cut up. One of the (so called) zombies launched himself upon a member of the Crypts, therefor biting him. The others stood there in shock for around a minute. Then pulled out there weapons and started shooting them. They only got one in the head, he fell (likely told in movies, makes you really wonder doesn't it) dead. But, as soon as that shout was sounded a couple other zombies turned the corner and attacked the rest of the gang members. As a result none of the gang survived. The one that witnessed this, went to the police, when they went to check it out all that remained was blood and the car...the only trace of evidence was a torn arm from the torso of one of the gang. They traced some finger prints, only to find that the person has been missing for a year.

In conclusion there are already sites of zombies but not announced to the world for fear of dramatic panic among the people...

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In Fort Jackson, South Carolina! Be back in November!

There are also more of these reported zombie attacks in the US. Also in other parts of the world, so the possibility of them already existing is a 76% truth the other is either not true, or a possibility...You must remember what a Zombie is refered as...It could be apart of voodo (Africa), or reanimation which is the likable term you are speaking of. I have done my research on this and I found that there was sitings of Zombies...

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In Fort Jackson, South Carolina! Be back in November!

I would say Global Warming as some or a few may know when 'Mother-Nature' gets 'ticked-off' it can cause more damage and on a larger scale than Zombies or Godzilla or whatever.

I choose the hands of God, but I also think it very probable for an alien invasion to stream down from the cosmos and destroy us all. And if they don't get to us first I bet we will fly on over to there planet and kick them out of there, just like we did to the Native Americans.

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"People should not be afraid of their governments. Governments should be afraid of their people." -V

Godzilla might actually work for Mother Nature, imagine that double-wammy. Earthquakes could give Godzilla an underground route from East Asia straight to the US, and all around the world!

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Educating the world, one blogger at a time.

It will be just as you have described (and it will be the cats, in the end....I can hear them laughing already).

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"A man's work is nothing but this slow trek to rediscover, through the detours of art, those two or three great and simple images in whose presence his heart first opened."

The creature would be spotted the moment it stepped close to a major city. Which by the time it ever got close to any cracks in the ground, we would have it blown to another world.

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In Fort Jackson, South Carolina! Be back in November!

Besides the Thundercats would take care of Godzilla and the G.I. Joes would help evacuate the citizens and fight off some of the Zombies.

It's common sense people. Godzilla is just a fictional charactor. Nothing so real about that. Zombies though, that is real. If you don't believe me than go ahead and look up zombie reports your self. I am sure you will find that I am right, and that ZOMBIES do exist though under scientifical evaluation.

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In Fort Jackson, South Carolina! Be back in November!