My main character is a Gloomstalker 3/Assassin 3/Shadow Monk 6 mix, but after finally getting enough Monk levels and gear to want to use only fists I discovered they don't work with the Gloomstalker extra attack, so I might change to just Assassin/Monk.

Character one I won't name because of spoilers is Eldritch Knight 5/Druid of the Land 7 because I wanted to keep them a fighter/druid for lore reasons. It's surprisingly decent to have access to Extra Attack, Shield and Magic Missile though. Obviously not an inherently powerful combo, but good enough.

Character two I won't name for spoiler reasons is Berserker Barbarian 3/Hunter Ranger 3/Champion Fighter 6 because I wanted them to be a Berserking Ranger for lore reasons and Battle Master felt too complex for that character. It does what you would expect, which is hit stuff hard and not much else.

I respecced Shadowheart to Life Cleric 1 and the rest in Lore Bard. Not really an odd multiclass but it's very powerful. Bless, Guidance, Heavy Armor, the Life Cleric healing buff plus the full bard experience.