Looks like someone played the "Fruity Oatey Bar" music around River again. So the inner weapon from when she was experimented on by the Blue Sun is triggered and she begins her rampage.
This was taken at Colossalcon 2014 in Sandusky, Ohio and inspired by the bar scene fight from the Serenity movie. I loved becoming River Tam and can't wait to do it again!
- River Tam