The Harmony Box

A box with six locks that grew at the Tree of Harmony.

-1
Discord's rebellion against Equestria in "Twilight's Kingdom" was actually planned by Princess Celestia from the beginning, so that the secrets of The Harmony Box could be discovered.

2
Rainbow Dash finds one of the keys to The Harmony Box during MLP:FiM Season 4, Episode 4.

4
The Tree of Harmony presented The Harmony Box as a result of being confronted by all of the bearers of Elements of Harmony, and the controllers of the sun and moon.

-4
The Tree of Harmony presented The Harmony Box as a result of the last bits of chaos being removed from Equestria.

2
The Harmony Box contains upgraded versions of Elements of Harmony.

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