Air Date: April 21, 2012
Part 1: Twilight is confused by her conflicting feelings when she finds out her brother Shining Armor is marrying Celestia's niece Mi Amore.
Part 2: Twilight saves her brother and all of ponykind by freeing the real Mi Amore and defeating Queen Chrysalis, a changeling that had assumed Mi Amore's appearance in an attempt to take over Equestria.
Official Discussion Thread
Watch MLP: FIM - Season 2, Episode 25 + 26: A Canterlot Wedding in 1080p HD now: