Which version is Thundurus (Sacred Form) in?

Question

Is it in Pokemon Black 2 or Pokemon White 2?

Answer 1

http://www.serebii.net/dreamradar/

Neither, you get Thundurus-T in the Dream radar.
From what I've gathered, he's not exclusive to just one version.

Pokemon Dream Radar will be released on the same day as Black 2 and White 2.