GamePlay Bug? Pulsefire Ezreal/Creator Viktor

I just finished playing a ranked game as Pulsefire Ezreal against a Creator Viktor in mid lane. AP Ezreal mid is my highest mastery champion, so I have some credibility here. For some reason my W (essence flux) was not doing damage at all to the Viktor. I even suicided, basically, into him to test it out with no luck. The ability was doing damage to the others from what i could tell just not him. It most likely didn't change the outcome of the game due to an AFK on my team, but it was still very annoying to play with. Please look into this!