User blog comment:Emptylord/Leaked Champion: Vel'Koz/@comment-5489694-20140124182201/@comment-5489694-20140126013603

The reason I could see Lucian fighting a Battlecast Vel'Koz is mainly due to the two tendril's on the left. They sort of appear to be charging/directing energy to their tips and that's sort of similar to Vel's ult (I'm assuming ult) animation/idea. It could be that the tendril has been recently damaged and is showing a residual burning effect though.

Something else that sort of just popped in to my head is that Lucian could be fighting multiple beings that resemble Vel'Koz. Vel'Koz probably isn't the only creature from the Void with the tenticular anatomy especially if Vel'Koz is actually tied to the Watchers, which sort of appears to be true.