Boss: The Fluttershy Effect

Battle theme: Luminous Avenger iX - Painful Determination

Reference to Luminous Avenger iX.

After the bad ending of Rainbow Gunvolt 1, Lightning Dust extracts Flurry Heart's brain and hooks it up to a massive machine called the Fluttershy Effect. It is the power source of LD's Falcon Quills and commits surveilance on and brainwashes ponies.

Flurry is crying throughout the entirety of Glimmering Avenger IX. As soon as Starlight reaches her, Flurry begs Starlight to put her out of her misery.

While looking for the Fluttershy Effect, Starlight refuses to even talk about it or let anyone else ask in-detail about it. Seeing how much Starlight cared for her sister Flurry in Rainbow Gunvolt 2, the Fluttershy Effect's existence gravely traumatized Starlight.

Befitting its name, the Fluttershy Effect attacks with laser-shooting copies of Fluttershy.

After Starlight defeats the Fluttershy Effect, Flurry thanks her as the machine explodes.

Starlight's sprite is by me

Fluttershy's sprite is from Mega Pony

Flurry's brain is Xaerous Brain from Gradius 1

Everything else is from the Mega Man series