My Little Pony: Friendship is Magic - "Kingdom Hearts"
* Not a real episode: "Kingdom Hearts" isn't an actual episode of My Little Pony: Friendship is Magic. There is no such episode in the show's canon. It seems like you might be thinking of a fan-made story or a crossover with the Kingdom Hearts video game series.
* Power in Kingdom Hearts games: In the Kingdom Hearts games, power is central. The main characters, Sora, Riku, and Kairi, wield the power of light to fight against darkness. They often encounter villains who crave power for their own ends.
Equestria Girls: Rainbow Rocks
* Power of Music: The main theme of Rainbow Rocks is the power of music and friendship. The Dazzlings, the antagonists, use their magical music to manipulate the students of Canterlot High. They crave power and control through music.
* Power of Harmony: The main characters, Twilight Sparkle and her friends, use the power of their friendship and their own musical talents to overcome the Dazzlings' dark influence.
* Power of Friendship: The film emphasizes that the power of friendship, kindness, and courage are stronger than any dark power.
In summary: While both "Kingdom Hearts" (the game series) and "Equestria Girls: Rainbow Rocks" feature themes of power and control, "Kingdom Hearts" is a separate franchise, and "Rainbow Rocks" focuses more on the power of friendship and music.