You can either wait for an Mystery Gift Event for Thundurus or trade for it.
No
You must trade from Pokemon White, which instead of Tornadus, it will be Thunderus. :)
You cannot obtain Thunderus in white by catching it. You must trade it in from Pokemon Black.
Needs to be traded from Pokemon White.
reshiram thunderus tornadus landours
thunderus is in pokemon white
You can't get Thunderus in Pokemon Platinum at all. By then when Pokemon Platinum was made, no one knew that Pokemon Black and White were going to be made.
trade. no other way.
Throw a pokeball at it.
You Don't Get Thunderus In Pokemon Black. You Actually Get Tornadus. To Get Thunderus, You Must Trade With Someone From White Version Who Has Him... (Tornadus, And Thunderus Are The Entei, Raikou, And Suicune Of The Unova Region, Meaning They Run Away Every Time You Enter Battle With Them. So I Suggest Saving Your Master Ball For Them.)
The only way is to trade from someone who has Pokemon white.
You catch Thundurus, but must trade Tornadus from Pokemon Black.