White Kyurem is the new mascot version of Kyurem that you can catch in Pokemon White version 2 on the Nintendo DS.
This new White Kyurem is Pokemon White version 2 specific, and can’t be caught in Pokemon Black version 2, which contains Black Kyurem instead.
To catch White Kyurem in Pokemon White version 2, you first need to get near the end of the game and get the Reshiram from beating N in Dragonspiral Tower.
Once you have Reshiram, head to Giant Chasm north of Route 13, between Route 22 and Route 23.
Deep inside of Giant Chasm, you’ll encounter Kyurem. If you’re able to catch Kyurem, a DNA Splicer will drop to the ground which you’ll want to pick up.
You can use the DNA Splicer to combine Zekrom and Reshiram into White Kyurem.
If you knock out Kyurem instead of catching it, you’ll have to beat the Elite Four to make it spawn again.