No, he is not. Cynthia is.
the sinnoh league champion. defeat her and become the champion.
The sinnoh champion Cynthia has one. She is located at the Pokemon league.
The Pokemon League after beating the Elite 4.
The Sinnoh League Champion "Cynthia" has a Spiritomb.
as soon as you become the sinnoh league champion
It is phantom, champion and zoroark but it's only released in Japan!!!
The champ is Cynthia.
Pokemon Sinnoh League Victors is Season 13.
On top of Mount Silver after beating the elite four, his name is red, litteraly
In the Pokemon league.
If you mean Milotic, if you want to complete the Pokedex it is nearly impossible to catch in Sinnoh. However, the Champion has one so if you defeat Pokemon League you will see it.
Your rival is the champion.