Jarvan is OP.
You never hear anyone complain about him. Yet he's constantly picked in competitive play, enjoys a good win/pick rate, and is incredibly powerful for how easy his kit is.
His attack speed steroid is absolutely absurd.
His level 2 burst is insane.
He can build bruiser, assassin, or tank, and excel at all 3.
He can defend turrets with modest wave clear. He can dive turrets with impunity. His W shield is massive if you hit 5 people. If he ever goes low in a fight he can drop his E basically anywhere and get free triumph heals.
Even if you build him tank, he can 75% someone with one combo.
If you build him bruiser, he can 100-0 a squishy.
If you build him lethality, he can 100-0 basically any squishy he ults, or multiple with almost zero counterplay.
I'm currently enjoying a 60%+ win rate on this champ because he's legit broken.
Until then, I'll enjoy my freelo train.