I already posted some of my favorite OP builds in another thread, but I had some build theory crafting. Anyone want to check my math?
The Electrocutioner
The Tempest Cleric / Sorcerer lightning damage combo is pretty well known. But I’m wondering what happens if we cross it with an Assassin.
The Assassin’s Ambush feature says it applies for any attack roll. Does that include spell attack rolls?
If it does, we can go Assassin Rogue 3 / Tempest Cleric 2 / Draconic Sorcerer 7 (lightning).
The Tempest Cleric’s channel divinity gets us max damage on lightning/thunder attacks. At level 12, we have 5th level slots. And the 1st level spell Witch Bolt deals 1d12 damage per spell level.
So the math goes:
Base damage is 5d12
Tempest max for 60 damage
(assuming target is surprised) Auto-crit, brings us to 120 damage
Draconic sorcerer feature adds CHA mod (+5 for 125 damage)
If the target is wet, double damage
For a grand total of 250 lightning damage on the first turn, which should one-shot most enemies. And this isn’t using any special equipment (other than maybe some water to throw), so you could probably pump those numbers a bit higher with special equipment.
And you can always swap out Witch Bolt for a Lightning Bolt for 130 damage to multiple targets (on failed saves, 65 on success).
This build would start coming online around level 6 or 7, and still be quite usable before that.