Whilst most marine life in the twilight zone is considered otherworldly and straight out of the horrors of one's imagination, there are more familiar names that you will likely have heard of. Equally as terrifying as any image you can concoct is the giant squid, for example. With eyes that are the biggest in the animal kingdom measuring around 10 inches in diameter, these enable this gigantic mollusk to see in the murky depths. These animals can even grow longer than a bus.

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Incredible facts you didn't know about the ocean's mysterious twilight zone