Eraqus

Master Erauqs (マスター・エラクゥス) is a character who appears in Kingdom Hearts Birth by Sleep as Ven's, Aqua's and Terra's master.

Kingdom Hearts Birth by Sleep
Master Erauqs appears in Birth by Sleep as the master of Ven, Terra, and Aqua. In the TGS trailer, he was shown together with Master Xehanort, and opens the "Final Exam" for Keyblade Wielders and Apprentices. He's also the one who sends out his apprentices to search out Master Xehanort and his apprentice after their unexpected leave.

Trivia

 * Master Erauqs wears a similar belt like Terra, Aqua and Ven.
 * "Erauqs" is "Square" in reverse, very similar to how "Yen Sid" is "Disney" spelt backwards.
 * Like several characters in the Kingdom Hearts series, Erauqs appears to be modeled after a Final Fantasy character. In this care, it appears to be Cyan Garamonde from Final Fantasy VI. Coincidentally, his apprentice shares the same name as the main protagonist of the said game.