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Original Description:

Here is the crazy and mischievous

Discord

In The Return of Harmony Part 1 and Part 2, Discord is shown to be a mischievous and manipulative trickster who effortlessly pulls pranks on others through the use of his powerful magic, illusions, and hypnotism with little to no consideration towards his victims. He has a sense of showmanship and drama, preferring to be playful towards his victims before getting down to business, as seen when he mocks and banters with Celestia and the Mane Six in Canterlot Tower. He laughs and amuses himself with his magical chaos, mostly at the cost of others. Among other things Discord turns the ponies against each other, making Twilight Sparkle miserable and depressed, and generally causes ridiculous things to happen.
Discord is arrogant and overconfident, as he underestimated the ponies’ ability to restore their friendship and wield the Elements of Harmony. Despite having a fondness for chaos, he can become easily annoyed if things don’t go according to his plan; he becomes impatient when he cannot corrupt Fluttershy as easily as the other ponies. In Keep Calm and Flutter On, Discord states that he’s never had a friend. He appears touched when Fluttershy declares herself to be his friend, and it is that glimpse of genuine friendship that causes him to undo the chaos he had caused. He states at the end of the episode that he will use his magic only for good from now on: “most of the time”. Since then, he has kept his chaotic tendency to a low, though is still more than willing to cause mischief.

Main cast and Discord group hug S4E26
Discord and his new friends.
In Princess Twilight Sparkle - Part 1 and Princess Twilight Sparkle - Part 2, he was shown to indirectly aid the Mane Six in defeating the plunderseeds, which he himself planted long ago in a bid to defeat the royal sisters. Even after the force that is most capable of defeating him is gone, he keeps his word to Celestia and does not go on a rampage, and he is rather easily swayed by Fluttershy. In Twilight’s Kingdom - Part 1 and Twilight’s Kingdom - Part 2, after he betrays the ponies of Equestria and Lord Tirek subsequently betrays him, he shows deep remorse for his actions and apologizes to Fluttershy and her friends upon realizing the true importance of friendship. When Twilight and the others forgive him and the ponies accept him in the end, Discord appears truly happy, which he expresses by giving Princess Celestia a bouquet of flowers.