A translation of a concept art page from Hyrule Historia. Images taken from History of Hyrule’s The Legend of Zelda art anthology.
Twilight Princess Concept Art
Design Sketches
The Beastial Ganon
The creature Ganondorf transforms into during the fight at Hyrule Castle. Perhaps the “Piggy Ganon” caption in the concept drawings is the staff’s nickname for him?
It’s ‘bestial’.