Applejack: A'ight, let's get this set piece rollin' already. Ah sit down in mah chair.
DM: Thank you. The apple Cutie Mark on your crystal chair glows.
Pinkie Pie: Oooh! Maybe if we alternate our sitting, we can get a sweet light show going!
Fluttershy: It's kind of nice, having a magical place just for you...
DM: Alright, I'll assume everyone does that. Once all six thrones are sat upon, the glowing marks shine their own colored beam of light outward.
Twilight Sparkle: Okaaayyy...
DM: All the beams converge in the conspicuously empty center of the room between all the thrones.
Pinkie Pie: Glowing signs AND laser light beams? This rave is gonna be off the chain!
Fluttershy: I don't really do well with flashing lights, so...
DM: Then rocks start jutting out of the floor beside the thrones.
Applejack: Woah nelly. Maybe Dash was onto somethin'.
Rainbow Dash: And after all that work to shut me down!
DM: They're not going for any of you. The stones draw trails towards the center of the room, where they all converge on the empty star. When they "collide," a strange thing occurs.
Twilight Sparkle: More strange than what's happened so far?
DM: The sontes seem to merge together and "carve" out a flat disc. They can hear stone grinding on stone as this polished mass slowly spins outward. Once it's big enough to fill the space between the thrones like a grand table, all goes quiet. And then... A magical, holographic map of Equestria appears atop the crystal table!
Applejack: So... we're the Ponies of the Round Table now?
Rarity: Please, no Holy Grail references this session, I beg of you.
I admit to cribbing this scene for a D6 Space one shot, for when the players figured out how to get the enemy command center on line. Unfortunately, they just went "Oooh, pretty" and ignored that the table told them where all the enemy units they were trying to avoid were located. Which led to yet another TPK.