“Back in Metalonia, it is not polite to scare weak man.”
— Karlof
Metalonia is Karlof's homeland, first mentioned when the imprisoned Elemental Masters were making the Roto Jet on Chen's Island. It was later mentioned by Karlof when he confronted the Sons of Garmadon. Metalonia, unsurprisingly, produces great metal and it's said that if Nya made her Samurai X Mech nowadays it would be made from Metalonian Metals.
According to Karlof in "Firstbourne," it is considered impolite to intimidate the physically weak in Metalonia.