This is the Allearth Forest/Chernabog and Yveltal's Story

This the scene where our heroes find this place called the allearth forest, and leonard tells the story of chernabog and yveltal in Team Robot in Pokemon: Diancie & The Cocoon of Destruction

(Later we cut the scene where our heroes are walking in the rocky hill, we view the mountains, later in the caves, Diancie heard something, she hops off rushing)

Dace: Princess Diancie!

Kristoff: Follow Me!

(As They Escapes the caves, Diancie See the View of the Allearth Forest)

Dash: This place is huge!

Bonnie: Wowee!

Victor: This is a biggest forest ever.

Skarloey: It's a Gigantic Water!

XJ-8: I don't wanna get rusted.

Eddy: So tell what did you see.

Diancie: I sense a strong Fairy Aura coming from inside the forest.

Serena: So, that means one thing.

Ash Ketchum: Xerneas!

Bash: That's why we need to find them.

Ferdinand: So, that's why we need to find them!

Coco: The Deer of X.

Finn: So, if I meet xerneas and End this nightmare?

Jake: We can't save the forest.

Dace: Princess, That is the Allearth Forest!

Leonard: The What Forest?!

(All of the heroes gasps)

Ash Ketchum: What's the Allearth Forest?

Dace: You see, long ago, there was a major catastrophe there that obliterated every living thing.

(Flashback plays with A Black Tornado appears Turning The Whole Forest into stone)