*I never did i just heard of it*
Don't worry, it's just Charades!
Rarity... is trying... to be... a superhero, rescuing Applejack, right?
In more than one way~
And as others have said, I love the atmosphere that the coloring style lends to this. That lazy warm afternoon feel.
I think these two have more cute/subtle interactions in the episodes than any others - most notably in "It's About Time" and "Magic Duel", as well as Sisterhooves and part 2 of the S3 opener.
Aside from that, it's your fault you clicked on the thumbnail. Welcome to the internet