The Last Stand at Red Hoof was the match that finally lit the fuse.

Before the smoke had faded from Manehatten, a proclamation was sent to the four corners of Equestria; Cadance summarily denounced Luna, the whole of her Republic, and reclaimed her title of Princess.

It was seen for what it was; a declaration of open warfare.

It was an invitation that Luna was not about to pass up.

When her aerial reconnaissance revealed to her the paltry size of Cadance’s army (composed almost entirely of New Dawn members and Crystal Ponies) Luna issued orders to General Soarin of the Shadowbolts to lead two divisions of the New Lunar Army to march out and burn the Empire to the ground. Messages between troops reveal that most loyal Lunar Republicans expected any resistance to be minor and the scuffle to be more of a slaughter than anything else.

Try to imagine their surprise when Shining Armor himself, now proclaimed General of the Army of the New Dawn, marched out into the snows, the full force of the Crystal Empire’s army behind him. The two forces set up camp at Leviathan Chasm, some twenty seven miles from the Empire's borders.

Still fully believing that any battle would be short, General Soarin had most of his forces remain behind to repair the train tracks (previously sabotaged by New Dawn forces fleeing from Manehatten) and entrusted the crushing of the enemy to Major Shatterpoint and several small platoons.

Within three hours, the platoons were decimated and Shatterpoint was dead.

Thoroughly embarrassed, General Soarin ordered the whole of his forces to sweep over the smaller army at once, hoping to take advantage of their weakened state.

Nopony expected Princess Cadance to reveal her first secret weapon; diplomacy. While many of Equestria’s neighbors had bent to proverbial knee to Luna, they weren’t about to pass up the opportunity, no matter how small, to restore order to the world and see the sun rise once more.

Three new armies descended to join the forces of the Crystal Empire; from the North came the tenacious warriors of the Yaks and from the East came the heavily-armed Minotaurs and the warrior-bred Griffons.

Suddenly, the odds were not evened. They were solidly against the New Lunar Republic.

The War for Solar Resurgence had officially begun.

An entire division was crushed in a matter of hours. Panicking, General Soarin ordered his forces to pull back to the walled city of Stalliongrad, the New Lunar Republic’s strongest Northern stronghold. By the time they managed to get inside and sealed the gates, General Soarin’s forces had been cut nearly in half. Even with those losses, General Soarin felt no fear. Stalliongrad had stood for nearly a thousand years and was said to be impregnable. He sent a message to Grand Marshal Rainbow Dash requesting reinforcements. That done, he settled in to wait out the siege, confident in his imminent victory.

One wonders what his reaction was when Grand Marshal Dash denied his request… per the personal command of Princess Luna herself.

Despite strenuous objections from her advisors, Luna stood her ground. She maintained that the remainder of the army could be put to better use strengthening defenses in locations closer to Canterlot, such as Sweet Apple Acres and the Everfree Field. The Last Stand at Red Hoof had shaken her, and she believed that any success incurred by the Army of the New Dawn, no matter how fleeting or small, could inspire others to take up arms against her. Trusting in Stalliongrad’s reputation as impenetrable (and trusting in General Soarin to a lesser extent) Luna believed that her forces could withstand the assault… at least until she could gather allies of her own.

Envoys were sent to Zebrica and the Dragon Lands; send assistance at once, or retribution would be swift.