How do I make black /white kyurem on xy?

Question

I got the DNA Splicers.
I got Reshiram, Zekrom and Kyurem.
Now, how do I make them 2 fuse together?

Answer 1

1. Go to Key Items
2. Use "DNA Splicers"
3. Select Kyruem
4. Select Reshiram/Zekrom
5. Kyruem changes form into White/Black Kyruem

Source

Follow those five steps, and your Pokemon will be fused!