In the One Thousand years Princess Luna was banished, Celestia grew accustomed to her solitary rule, and when Luna returned, was reluctant to relinquish such power.

Luna herself, did not care. But there were some of her subjects that saw this as unfair, and protested.

They were ignored or arrested, Celestia was quickly branded as a tyrant by the protesters, and the New Lunar Republic was formed.

In the Republic's first few years, Princess Luna called for calm, and tried to persuade them to disband.

When she failed, Princess Celestia tried more violent ways, executing many of the NLR's supporters.

Then Luna joined the Republic, seeing these executions as her sister trying to consolidate and show her power.
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Sky Dancer and Split Second have been friends since flight school, but with the war approaching, they have different opinions on the opposing factions. What happens when two friends go their separate ways in such circumstances?