Quick showcase of running a self Galvanic Field that stacks Phantasmal quality. Not a cheap build because it uses Ashes unfortunately, and it's a pretty mandatory item on this.

Mechanics:

Galvanic Field procs when you next shock something. It scales damage and area based off the strongest shock currently on the target when you shock the target, not the shock that procs Galvanic Field. In addition, Phantasmal makes the area scale even more based off the magnitude of the shock. So we run a Voltaxic and Shock Mastery to get 105% shock magnitude, and use Vessel of Vinktar to hit that magnitude on ourselves (50% base shock, so you need 110% increased shock effect to hit 105%, including the amount on the flask). Vinktar's doesn't proc GF though, so you need to hit yourself with something that shocks you, which in this case is Herald of Thunder with Storm Secret. The shock does not need to stay active in order for the GF to continue, so after we apply the GF we use an immunity to shock for X seconds if shocked flask to remove it, attempting to tie that duration close to the GF duration (not something I've done yet). Finally, to safely cast it without being near mobs, we hit worms with the HoT instead of risking going near enemies. You still need a very high chance to be shocked, so Divergent Conductivity inside a Rotblood takes care of that since we're using Ashes. The whole setup takes about half a second or so to get going generally.

Current issue is the build is still too squishy, and single target still isn't super amazing. The solution here would be fixing my main flask to have shock immunity, adding Progenesis, and using Petrified Blood, but still haven't done that. Also, the explodey is nice but sometimes messes up our procs, as you can see when I messed up the proc and lost GF on myself at ~1 min in, so I had to proc it with Shock Nova until the immunity flask ran out.

I'm using Dance with Death since it gives 62% more damage. Using a helm would likely be a better choice, especially with the +1 chain enchant since you could potentially swap out the Chain gem (especially if using Forbidden Flesh/Flame to get the +1 chain from Deadeye). There's also probably an approach here to use Templar and the uber Forbidden Flesh/Flame jewels (only 1 divine) with Forbidden Rite proccing the shock, to avoid having to maintain Vinktars. If you want to go full meme, you could take this approach, go Inquisitor, snapshot the shock with Voltaxic, and then weapon swap to an Annihilating Light to pop the Galvanic Field and get silly damage. I was hoping this would work with self temp chains, but it looks like temp chains doesn't increase the duration of Galvanic Field, which is a bit odd.

PoB: https://pobb.in/RjpAYuIxpkEq

Aspirational PoB (needs tweaks and wouldn't work in its current state, and would rely on a lot more button presses to swap out Conductivity): https://pobb.in/YAWV1YbodVGh