As you may have noticed, Viktor has been disabled most of the day today and the, unfortunately, RiotRival just broke the news that he will remain disabled until a fix can be deployed in the next patch.
"Due to a bug we have been temporarily disabled the champion Viktor. We have identified the problem and are working on a fix.
We apologize for the inconvenience. Check back here for more updates.
12/10 18:00 PST - Viktor will remain disabled until the next patch. Sorry for the inconvenience"