Vayne/Janna bot.
I've found since the 7.19 patch I have not been able to Dent or slow down Vayne when she is teamed up with janna, it's like they are a unstoppable Bus of death. since this patch has aired I have lost 3 for 3 vayne to the point where it didn't even feel fair, 2 levels ahead with Serious amounts of kills on a vayne, and I still can't Kill a vayne 1v1 atm, as evelynn. million mastery eve, feels a little Excessive, especially since janna can E faster then my E can trigger.
The real problem is Together, Vayns movement goes from between 370 to 530 in a drop of a hat, depending on how shes facing so you can just Turn and poke off every engage, and with her Q hurting as much as a turret shot after a tumble it's pretty intense.