I posted this in the forums but I felt like spreading the word a little more.
A hidden champion has appeared in Battlecast Vel'Koz's splash art.
Forum Thread: http://forums.na.leagueoflegends.com/board/showthread.php?t=4284301
wow good eye
Could be battlecast kog'maw, could be anything, could be nothing. I vote for it being a champ named Rorschach. ;)
Interesting to speculate about, but until we know more, it's only speculation.
I felt it was a hint to a possible upcoming battlecast 
, since an ANV code was originally in the battlecast 
blueprints.
Edit : lolwiki trivia about cho'gath : In the spoiler for Battlecast Cho'Gath, in the top right are the names XER
, URG
, SKA
, MAW
and ANV .
