Doing a warforged caster arty, really fun!

Do any1 have an idea of the best runearm for endgame (lvl 30). That has a big aoe for immunity removal + big aoe for breaking boxes cause i like that + nice damage?

Most imortant big aoe
second: good dps (for being aoe runearm)
third bonmus: break boxes!

And one that is easy to target or cone etc. Not a single exploding shot that has no homing so me that is **** targeting that always miss :-)