From the Super Mario Wiki
“Who has awakened me from my eternal slumber?”
Yikk, Mario & Luigi: Bowser's Inside Story

Yikk is a character that appears in Mario & Luigi: Bowser's Inside Story and its 3DS remake. When Bowser enters the Tower of Yikk, and reads through a book he finds on a desk, Bowser's way out is blocked, and Yikk appears from the book as his undead form. Yikk claims he invented the Tower of Yikk and the Boo-ray Machine. He created the Boo-ray Machine to study Boos and other spiritual beings. After Yikk explains his machine and how to use it, he shuts the book, and goes back into slumber.

Yikk is similar to the recurring character Professor Elvin Gadd: both study ghosts, and both their names are puns on exclamations ("ick" or "yeek" for the former, "egad" for the latter).

Names in other languages[edit]

Language Name Meaning
Japanese イビッキ
From 「いびき」 ibiki (snoring)
Spanish (NOA) Yikk -
Spanish (NOE) Fantómasen From Fantasma, meaning Ghost.
French (NOE) Ronfloski From ronfler, meaning to snore. It looks like a Russian name.
German B. Huubert Pun on Buu Huu (Boo's German name) and the male name Hubert
Italian Yikk -