1. Manabond, lightning spell with bonus damage and range based on high/low mana.

2. Mjolnir, triggered lightning spells on hit cost 0.

3. Indigon, gain spell damage % based on mana used recently.

Use melee skill attached with mana leech (?) and other regen + spend methods. This triggers Manabound for 0 mana.

To ensure that mana drains instantly, we can use CoC/CwC linked with spells. Even with low level gems, Indigon should increase the mana usage enough to keep Indigon topped off. If we need help starting the Indigon loop, throw in an arcane cloak.

Add flat element damage sources which are then multiplied by Indigon.

We stack mana regen sources as much as possible.

I'm not sure if it's require to have something that makes cyclone cost 0, for QoL.

What you end up with is high Indigon uptime, 0 cost spell on Mjolnir that scales off missing mana, and buffed CoC/CwC spells that fire occasionally.

Are there any major flaws to this idea?

Edit: Trickster is very good for this build. You can also get insane amounts of mana through leech increase nodes. Have to test out PoB if I can hit the 4000 mana/s cap.

Edit: Super preliminary build

https://pastebin.com/GbxDpaJS

Somewhere between ~~5m-6m~~ 3m DPS (using shock nova to simulate, expected to scale down damage). ~8000 ES. ~10000 Mana. Ivory Tower Heiro build with low-life. ~1000 Mana regen/s + ~3000 Mana leech/s against single-target. One issue that the Heiro has vs Trickster is that cyclone will cost some mana. Hopefully this isn't too big of an issue in practice with enough regen. Lots of room for optimization