Build Guide
This build, if done correctly, will have over 50% chance to stun on hit whilst hitting enemies over and over (by use of the helmet's effect) to basically guarantee a stun. The Stun Wizard's build does not focus on damage (though it doesn't lack behind many other builds), instead we focus on controlling the field and making it so the enemies cannot attack in the first place. You will utilize Tal Rasha's set bonus for damage by casting blizzard and meteor. After you've accumulated the full bonus from the set, you will only be using Energy Twister and Electrocute. This (combined with Delsere's Shame) Will allow you to do this combination theoretically forever. This will give you three lightning attacks on the field at once, Electrocute to stun, The Twisters to be your main damage output and the Energy balls just for a little more dps/stun chance. Using this combination, you will find that most enemies cannot even move after you start the electrocute/energy twister combo.
This build (At least my character) can run T10 Solo. They do not have the massive amounts of damage, so you will usually only have about 2-4 minutes left at the end of the rift. They (sometimes) can struggle with the rift guardian, but this can be overcome by finding more enemies. When you have at least two enemies, your electrocute will chain back and forth from them, almost guaranteeing a stun on both of them. The reason they may struggle on rift guardians is due to the lesser stun chance on them. But, if you already have the damage bonus, Using energy twister with electrocute constantly will bombard them with 3 electric attacks every cast. (The Twister, Ball of lightning, Electrocute) and each will have about a 50% chance to stun. So if you have the mana, you should be good. This is why we have unstable anomaly. In the event that the rift guardian can move, they'll probably only get one or two attacks in. If those attacks kill you (or would kill you) unstable anomaly will save you.
Just keep stunning, just keep stunning...
This character is a HUGE HELP in group rifts at T13 or above. Their ability to stun entire groups of enemies and blue or gold bosses is invaluable. Melee characters will no longer have to worry about getting surrounded or hit too many times with the Electric Stun Mage there. It kind of takes a (usually) tense rifting experience into a much more playful and relaxed rift. People don't have to be watching the entire screen for those stray enemy fireballs and attacks, because you stop them from attacking in the first place.
I forgot to mention, choose whatever shoulders you want. There aren't many that are helpful to the build.