Volibear is ... dare I say... overpowered!!
Well here are some facts to consider:
Volis q does bonus damage and "hard" ccs the enemy if you count flipping them over and slowing them (atleast i think it slows) It also grants him 30% bonus movespeed TOWARDS CHAMPIONS at level 1 !!!!! , without a champion it is still an amazing 15% boost.
His w is where the magic happens. He's listed as a fighter (primary), and a tank (secondary) Pretty sure this is maxed first, but for comparison, at level 1 you get 8% attackspeed per stack and at level 5 you get 20% per stack. That's 4% less than a guinsoos and like I said, this ability is usually maxed first. Best part is: It's an execute (hey fighter) and it also scales with 15% of your bonus HP. I consider myself to be fairly decent at kiting and volibear running at you with simply a cinderhulk and some boots is basically unkitable. You're attempting to avoid his flip, which lasts a long time, and then you have to 1v1 him unless you have enough attackspeed to just run around and attack at nearly the same time. The only adcs which come to mind that are capable of doing this are either vayne or kalista. Kalista does potato damage when his passive is popped, since it basically rends her rend useless ( hah ) and vayne is plain out broken and can condemn him/stealth for 2 seconds w/ a true damage passive lol His e is probably the only thing I'd say is balanced, b/c his passive is on a two minute cooldown and volis don't give a shit if they use it in the JG because after one run it'll be back up, and his ult lasts for an absurd 12 seconds with aoe magic damage (75 at rank 1).