The launch of the 2.0 update has opened up new possibilities in Path of Exile, including new interesting builds that could have old players come back to the game and new players intrigued. Some of these new build possibilities may only make sense if the player has had some significant experience with building different kinds of characters, while others are easy enough to understand for anyone who is familiar enough with action role-playing game concepts in general.
This build in particular is for those who just want something simple to play with. All you have to do is to throw ball lightning all over the place, and that is all there is to it.
The Ball Lightning Shadow is exactly what it says on the label, a Shadow that just casts Ball Lightning at enemies for big damage. It is pretty easy to spec and get Path of Exile items for and more or less foolproof, which is great if you are the type of player who does not like getting bogged down by details.
But if you are a Path of Exile veteran who wants something to play with in returning to the game, then this should be right up your alley as well. This is especially great for those who like to play solo, and you do not need to trade so much to get the gear you need, just in case you are not one of those social players and just like grinding alone.
The key is Ball Lightning itself, linked to Increased Area of Effect, Spell Echo, and Lightning Penetration. That's right, the foundation of this build is on 4-linked PoE items, so there is no excuses here. If you have a 6-linked item, then you may strengthen it with other support gems if you wish.
As for other stuff, you can put Tempest Shield, Arctic Breath, Cast when Damage Taken, and Greater Multiple Projectiles on another 4-linked item to help with your Ball Lightning and your defense at the same time. Put Conductivity, Curse on Hit, and Herald of Thunder on another item, and then Herald of Ice and Flame Golem on another for some extra damage because that never hurts.
As for the skill tree, the important nodes to take are naturally Elemental Damage and anything else related to your casting prowess, including Trickery. You may also want to get Blood Siphon, Soul Siphon, and Coordination as well before going off to take more casting-related nodes in the mostly Shadow part of the passive skill tree. Energy Shield, lots of Lightning Damage, and all the defense nodes you can get are recommended as well, of course.
That is pretty much the gist of the build. Just power up your Ball Lightning with lightning damage, get a bunch of life and energy shield, a little bit of crit, and you are all set. The power of Ball Lightning on this build is such that you may find finishing the game at Normal difficulty to be a bit of a breeze and getting through the subsequent difficulties to be fairly manageable as well.