The Artist’s Description AKA THIS IS WHAT JAX5485 REALLY BELIEVES:

“I used to look up to her as my teacher, she was a mother to me. But then I found out the truth, the truth about Luna’s transformation to Nightmare Moon, the truth about Applejack’s parents, the truth about having knowledge of the Queen Changling posing as Princess Candace and Trixie’s arrival, and the truth of making me an Alicorn knowing it’ll make me outlive my friends and family.

She lied to me as she lied to all of us and my friends, both pony and human. But no more, her days of rule over Equestria are numbered and we’ll overthrow her and replace the kingdom with a new republic that practices true democracy, liberty and freedom.

This is Twilight Sparkle, Unicorn Pony and sergeant of the 1st Battalion of the New Equestrian Army.”

This is the art that takes place in the ‘Lost in Equestria’ timeline where Humans transported to the Equestria Universe and the Changling Invasion sparked off a chain of events that eventually lead Equestria into a Revolution. And the weapon in her hoof is an Hoofer M4A2 Carbine assault rifle designed for ponies to use.