Discord hid the Elements of Harmony after taking them from your teacher Princess Luna and hid them. you, Rainbow Dash, Rarity, Fluttershy, Pinkie Pie and Applejack. He affected them and made them the opposite of their elements but eventually you got them back to normal. You six finally got the Elements and confronted Discord who was making chaos in Ponyville.

Discord: "Oh. You and your little friends finally found the elements. I guess this is the part where you talk about friendship and turn me back to stone aren't you? Well you won fair and square."