To fully detail it, it's a slight variation on Battle Factory where you only select one rental Pokemon out of a selection of three and join up with two other NPCs who have their own Pokemon that you'll also control.
Once you begin, you go through three consecutive battles and obtain Festival Points depending on how wellyou did. Winning all three causes you go up in grade level and earns you a Rare Candy.
At Grade 1, all three rental Pokemon that are selectable, as well as all opposing Pokemon, are set to level 50. Each grade increases the level by 1. The levels of the two NPC Pokemon are dependent on the grade of the players you chose to join up with.
If you play the game without ever communicating with other players, you're forced to use two level 50 Pokemon regardless of your grade.
You get to wear some slick shades.
It's the easiest way to grind up your Plaza level.
I think that's about it.
