User blog comment:Pogingjose/Lightning Tournament/@comment-25251916-20141004061643

It was known as the Thunder Arena Vortex. It had the similiar function as the Fire Arena Vortex where you could only have a certain type to fight in the arena. It was first released about August 25 but it was later disabled after some difficulties, I suppose.

People are still awaiting for it's return but it hasn't happened for over a month now. It's also a thing that people like to use to complain to Gumi for delaying it.