Xelor (also known as Xelor's Sandglass) is a class.
Xelors are magi who can influence time. They also command obedience from all related mechanisms like chimes, clocks and pendulums. Therefore, Xelors enjoy playing with time... either to slow down their enemies or to teleport themselves wherever they want.
Xelor backwards is Rolex, which is a watch brand, and the Xelor skills have a lot to do with time.