I've noticed a pattern in URF - champions with knockups and shields dominate.
There is literally NOTHING you can do. Yeah, 25% tenacity. That's great. Real nice. Your heals are reduced? Enemy shields are not. They benefit from the tenacity and have no trouble escaping, but you are stuck permanently in the air. Literally. Blitzcrank's fist is a 1 second knockup on a 5 second cooldown. Xin Zhao's too (and he reduces the cooldowns as he attacks). I have been relentlessly stomped every single game against a riven with her going around 30/6 KD each time. If you get Riven, you can't fail. Ultra Rapid Fire? More like Ultra Rapid FuckMeInMyFatPuckeredAss.