From the Super Mario Wiki
Silver Door Spirits are living, horned, silver-colored door knockers in Horror Manor in the game Wario World. Like Door Spirits, they shoot bolts of electricity at Wario, but they differ from their brass-colored cousins in that when they take damage, they will charge up and shoot a much larger and more powerful ray of electricity. Wario must dodge to the side when this occurs.
Names in other languages