I'm running a Curse of Strahd campaign and one of my players just hit level 3.
He told me he could do a blow causing 61 damage.
That just didn't feel right.
This is how you could do it assuming his blow would hit.
Using a longsword: 1d10 (longsword) + 2d8 (divine smite) + 2d10+3 (poison strike – Oath of Treachery) + 2d6 (thundrous smite)