Since the trailer is out, I can tell you a few things

- Repel will not work with steps anymore, but with time. Repel is 0:30 seconds, Super Repel is 1 minute and Max Repel is 2 minutes. You can use any repel as much you want in order to increase the time.
- Guzma is Giovanni's cousin and Plumeria used to be a punk girl from Kalos who witnessed the events that happened in X/Y with Team Flare.
- Ash-Greninja is in the game. It has two abilities: Protean and Mold Breaker.
- Speaking of Ash-Greninja, the mechanic will also make its debut in the game. In Pokémon-Amie, you were able to get a maximum of 5 hearts. Now, you'll be able to get 6. If you get 6 hearts, certain Pokémon will be able to get this form". It's officially called Synchro Fusion and Ash-Greninja will be called "Synchro-Greninja". Dragonite, Wobbuffet, Luxray, Delphox and Chesnaught are one of the few Pokémon you can Synchro Fusion with.
- On the topic of Synchro-Greninja, a few Pokémon will have two abilities. Some Synchro Fusions and Zygarde.
- A Battle Tower clone will return with the name "Battle Park". You can fight the strongest trainers from past generations.
- Mega Evolution will return but it is post game. Only a few Gen 5 and 6 will get Mega Evolutions.
- The Z ring will not work on Mega Evolutions, Synchro Fusions and Zygarde.
- The Surf minigame from Yellow returns.