mane_six_(my_little_pony)
The main six characters of My Little Pony: Friendship is Magic - Applejack, Pinkie Pie, Fluttershy, Rainbow Dash, Rarity (my little pony) and Twilight Sparkle.
Use this tag if all six characters are present and they are the main focus - this tag shouldn't be used if they're just in an everyone-type post.