Tiamat looking proc on multiple champions

I do not know how to recreate the visual bug, but it keeps happening. I tweeted to riot support on twitter and they told me to come put it here. I saw it in my game once, and I thought it was just something once happening, big whoop. Then I saw it again and again, but then I saw it on Rift Rivals, http://prntscr.com/fvuxhr https://www.youtube.com/watch?v=wrUwzVaH0ss&feature=youtu.be&t=47m41s in the video, its right as Bjergsen as Galio dies. https://prnt.sc/fvg2mq heres another one of it on a lee sin. This has been happening for a few weeks now.