Nature: The Kraken!

An unwary ship passes through the North sea, when suddenly the water erupts as four huge tentacles shoot out and grab the the ship, the crew soon realise that the kraken has got a hold of them and they know they won't escape. The Kraken is mainly recognised by its colossal tentacles and eyes, but if you hang around for long enough you will discover its powerful jaws.

I chose this creature to create because I love Mythical Beasts, especially huge ones like the Kraken.