It also means all the gym leaders will use only Isshu pokemon.
Luvdisc's evolution, what? Strange :/
That. It hasn't been confirmed to be an evolution yet, but it looks just a little too similar not to be.
I'm guessing one of these options is correct:
1. there will be roughly 140 entirely new pokemon that will be obtainable prior to the Elite 4 challenge. The Generation 1-4 pokemon and about 15 new, Generation 5 pokemon connected to them will then become avaliable.
2. Pokemon like Luvdisc, with connections to the 5th generation will be the only old pokemon obtainable before defeating the Elite 4/obtaining the national dex. On the grounds that they evolve into an Isshu pokemon.