I've had two instances of really weird, unorthodox, but amazing units.
The first, was HHM Guy in FE7. He's already decent, with HM bonuses and all that junk, but this Guy... was special.
He grew Str literally EVERY SINGLE LEVEL UP. To the point he capped it at level 16.
He missed one single level of str.
I promoted him soon after, and he then proceeded to squash HHM harder than Ryoma does on a Normal mode Birthright run.
The second, was, bizarrely enough, a generic Sorcerer, in Lunatic Birthright.
It was around chapter 23 (The Camilla one), and I was using Witch Orochi, because I wanted SOME type of magic user, but she was the only one I had...
So, I thought "hey, there's a skirmish around. How bout I grind a little and capture a unit or two?"
This was my first encounter with Lunatic skirmishes, and I was... shocked.
The enemies weren't just equal to my army, they were BETTER, than my army.
To the point where it was normal for their ratings to be above 130.
On FUCKING GENERICS!
I captured a level 9 Berserker, a level 10 General, a level 9 Paladin,
and the god that was this generic.
The boss was a level 14 Sorcerer, with 47 HP, CAPPED MAGIC, mid to high twenties in everything else but luck and Res, those being 7 luck, and THIRTY TWO RES!
He also had the skills Heartseeker, Vengeance, and Bowbreaker.
Suffice it to say, I captured him, and after pairing him up with Silas, he slaughtered the rest of the game with a forged Snake Spirit and a Nosferatu (which I got from My Castle rewards).
His name, was Roderick.
And he was a god among men.
So yeah, that's my story.