Oh man just found my current fav build I've run into.
Spear. Chain lightning from my attacks and cast. Ramp up how many times chain lightning bounces. Add on jolt effect from lightning. And also support fire from Artemis who shoots out a homing arrow any time I attack, cast or special. Shit just dies all around me.
Edit: Just added Flurry Cast to this. And then my first two Legendary ones. Fire electric bolt anytime I use an electric boon lol. And +2 to cast.