PvE - Shatter with angry magic and bloom. The tracking allows the smaller bombs to track enemies away from the center, effectively increasing the blast radius of nova bomb (beyond that of even vortex with annihilation). PvP - Vortex with annihilation and vortex mastery. Because it's a one shot, tracking shouldn't be needed. Vortex is used for the tick on people that don't get hit by the initial blast, and it can also be used for map control.