Majora's Mask What Makes a Transformation Mask?

[CheeseXCrackers]

You had to play the Song of Healing to get the Deku Mask, Goron Mask, and Zora Mask and they're transformation masks, but you also played the Song of Healing to get the Gibdo Mask and that wasn't a transformation mask (I thought it was going to be, though). Maybe you need to help someone pass onto the other side with the Song of Healing. Darmani was a ghost when you met him and you helped him pass on with the song, and Mikau was dieing when you met him and you helped him pass on with the song, but what about Kamaro? You met him as a ghost and helped him pass on with the song, but his mask wasn't a transformation mask.
So what makes a transformation mask?
(Let's not count the Fierce Deity Mask because that mask was more of a bonus.)

 

[The Jade Fist]

Link steals their souls.

not joking either.

The deku mask is the imprisoned soul of the dead deku at the beginning, and the other masks are from the goron/ zora's soul.