Magician's Sacrifice Elemental spell has been replaced completely. I decided it made no sense at all to have a skill that kills the centerpiece of your class. Instead it is now a spell that you command your pet to do. The skill is different depending on what pet you currently have:

Earth: Roots all targets
Air: Single-target lightning attacks
Fire: AE fire novas
Frost: Funnel cone of frost type of attack that freezes up to 3 targets