Vi Bug
So during a team fight, (i was morg, my friend was Vi) I had snared the alistar and Vi had line of sight on the graves. I black shielded him and he pressed R. What happened next we dont really know, Vi's ult line came up and the animation started although not much else happened after a few seconds of her slowly walking towards the graves the animation somewhat canceled but she couldnt cast abilities or use summoner spells, then when walking close to graves the last part of the Vi ultimate worked and then she was free to cast moves. Obviously during this time and confusion and not being able to use abilities we got destroyed in the fight and lost the game seconds after. There is a link to a video i saved from the time in question, hope it helps to see this bug removed and not cause any more ranked losses :)
Tonkymac