Microsoft will be at PAX Prime this weekend with Xbox One, games, “surprises”

[Wright]

Zappykins said:

It's going to be a new game called 'Jurassic Park Adventure Time' A blend of Dinosaurs, the original Adventures game with many adventures reflecting the adventures of Fin and Jake. 

Here is a secret shot of it. (Note: Sean Penn is optinal.)

By optional you mean paying DLC.