This is my rough outline for my planned Thea 1 Split Lightning Bolt Build.
Inside you will find item suggestions to guide you, as well as a few different trees based on where you might be in your progression.
Slate are simply examples of some of the more important mods for you to be on the lookout for.
Use the best pets for you, don't fomo over what you don't have.

VERY IMPORTANT - DO NO TAKE A N Y +Max Focus Blessing mods anywhere on your character. It will brick the Hero Trait. Only stack agility blessings, they will be applied to your focus blessing.

Hero Trait Order: 45 - Predicted Justice | 60 - Prophecy of Punishment | 75 - Predicted Reincarnation
I prioritize getting to Prophecy of Punishment ASAP to get Lucky to make the build feel much smoother. The damage range on the skill is VERY large.

Use the best pets you have for the build, please don't FOMO over what you don't have. Iron Lion, Weaver, Squiddle when spell burst are all great. But if you've got good purples throw them in. Esp if ranked up they offer a good chunk of damage. Destines early should just be Int for both small and medium unless you REALLY need to fix something else in the build with a bandaid.

You will play as Tangles until you can get your spell bursts automated. This can be done with:
Solid RiverSRSolid River Helmet
A Netherking's Banishment special slate
Activation Medium: Spell BurstSBActivation Medium: Spell Burst