Both Chesnaught and Serperior are grass starters that have a "medieval europe" theme for their concepts. One is a knight, the other is european royalty.
Whose design do you prefer?
Who has the better pre-evolutions?
Who would win?
Who do you prefer?
Other Kalos vs Unova Starter matchups:
Delphox vs Emboar
Greninja vs Samurott