I'm sure that Asmodean was killed by Lanfear, Daughter of the Night, using the True Power so that Aviendha or Rand(sensing the goose bumps) would not know how he died! Asmodean fears Lanfear more than the gholam,Fain, any other Forsaken, or Shadar Hairan other than Shaitan, so I figure she killed him and is now waiting to try and kill Rand and the best way to do that is to kill off the one teaching him so he can't get any stronger because she is obsessed with being stronger than him. She escaped through the Tower of Ghenji when the ter'angreal exploded, now she will return and destroy!