Master Eraqus is a Keyblade Master featured in Kingdom Hearts Birth by Sleep and Kingdom Hearts Birth by Sleep Final Mix. He is the master of Terra and Aqua, and he also serves as the second master of Ventus. His name is an anagram of "Square", a reference to Square Enix, the developers of the Kingdom Hearts series. Tetsuya Nomura stated in the Birth by Sleep Ultimania that he had actually forgotten the basis of the name, and that the producer had to remind him that it was an anagram.