Sion lag bug when using Q

While playing Sion I noticed i was having a lot of lag problems, which frustrated me because I NEVER have lag problems. After restarting my router, making sure no one else was using my internet, ect. I realized it was only when i used his Q. That basically it, it happened in normals and in custom, i didn't want to try it in ranked. I tried other champs and none had any lagging issues.