A nosy bookworm, a put-upon carrot, a neurotic apple, a giggly airhead, and a pegasus who's all wind and no thunder. Put 'em together and what have you got? No idea, but Twilight's about to find out the hard way.
Long, long before Equestria, ponies in that land lived in a number of smaller kingdoms. Princess Essenta, the first daughter of the Dale, sets out to prove herself when her father, the king, sends her on a poorly conceived "suicide mission".