Catch octopus in the sea with a net. Octopus, also called octopus, is a mollusk. When catching the sea, you can dig octopus in a small hole in the beach. In addition, according to the octopus's habit of drilling into shells, it can drill a hole in the shell, string it up with a rope and sink it to the bottom of the sea, and then pull it up after the octopus gets in. You can also copy and scrape with a net.