User blog comment:Zurre2004/PE Proposal: Majora/@comment-38954675-20190610192336/@comment-26120048-20190611111950

"First Majora, curses Link into his Deku form, (basically shapeshifter mode locking him into that form until he learns the Song of Healing after recovering the Ocarina."

-> I think this can be attributed to a tasteless prank from Skull Kid and not to the mask.