Yuumi Invisibility "Exploit"
It's becoming a common strat now to play champions with invisibility as Yuumi's teammates so that all of Yuumi's abilities become invisible. Yuumi using abilities will not reveal the champs she is attached to so she can apply dmg and slows freely while being invisible the entire time.
If this is an intended effect for Yuumi then she will never survive the ban phase again. Invisibility is already a touchy subject and now making Yuumi the strongest invisible champ is making games with her in them unplayable.
This should be considered an exploit at best and I believe it needs to be fixed ASAP.