Monk of the Storm

 So, fun fact, my first post-2024 character concept I came up with was a Goliath Warrior of Elements Monk. The concept was that he was from a flying city (ancient cloud giant runestones keep it aloft) and a crew member (sailor background) on an airship that flies into storms to collect elemental energy.

This concept actually works really well in Eberron, perhaps minus the flying city. But I realized there was a way to make it really powerful by level 8.

First off, we find a way to get Mark of the Storm as our origin feat. We could make him a House Lyrandar heir as his background. This will allow him to boost his Dex with the background, though it doesn't help Wisdom, which is a little tough as I generally want +3s to both at level 1.

Now, Monks are a lot better than they were, but they still don't quite overcome characters with powerful damage-enhancing spells. But now we can! And it's even quite on-theme.

We'll take some appropriate Dex feat at level 4 to boost our Dex from 17 to 18. Then, we take Potent Dragonmark at level 8, which is, conveniently, the level at which we'll get a 4th level spell slot from it.

This will give us access to Conjure Minor Elementals (hey, we're an Elements Monk). Now, each attack we land within 10 feet of us will hit for 2d8 extra damage.

And while it does cost us our action to cast this spell, we can immediately Flurry of Blows to make two attacks. At this level, that's two attacks that are each doing 3d8+4, or 17.5 damage each, or 35 total.

But then, on subsequent turns, with another Flurry of Blows, we can hit four times, meaning 12d8+16, or 70 damage.

At level 10, we get two upgrades: our Flurry of Blows now does one more attack, and also our Conjure Minor Elementals will get upcast to 5th level. So, now, on turn two, we're doing five attacks that are each hitting for 4d8+4, or 22 per hit, giving us 110 damage.

Obviously, this is just damage potential, as this assumes all attacks hit. We're also slightly delaying our Dexterity progression (though we can boost Wisdom with the Potent Dragonmark feat, so we're still getting something we'd want to boost anyway).

At 10, barring Wraps of Unarmed Prowess (though I'd hope our DM would give us some) we have a +8 to hit. Against a target with a 15 AC (weirdly common at level 10, even if that feels low) we would have a 70% hit chance.

So, we have 22x70%, or 15.4, plus 18 (our extra damage for crits)x5%, or .9, giving us 16.3 damage per attack.

Thus, on round one, we're doing an average of 48.9 damage, and on subsequent rounds we've got 81.5 damage, and that is pretty damn good if you ask me.

We will only ever be able to do this once per day, but I think that's fine - this is our boss-melting move. Given that we're likely an Airship captain, this is our "GET! OFF! MY! SHIP!" move.