Jabun
Jabun is a giant fish who is the Water Spirit. He can only speak Ancient Hylian. He used to live at Greatfish Isle. Before Greatfish Isle was destroyed, he sensed Ganondorf coming and fled to Outset Island. Then, the King of Red Lions and Link came in his cave. Before they left, he gave Nayru's Pearl to Link.
It is likely that Jabun is Jabu Jabu whose name is now pronounced differently when spoken with the new language.