Oni are demons, usually shaped like humans, with sharp claws and long horns.

They often carry an iron club, and the phrase "oni-ni-kanabo" (oni with iron club) is a common way to say "invincible".

Waves too are Maori styled but they take over the ones of Japanese styled storms, and the symbols used for the demon decorations indicate strength, adaptability and protection (nowadays onis often have a protective connotation).