Sonata Dusk

Sonata Dusk is a female siren and one of the main antagonists in My Little Pony Equestria Girls: Rainbow Rocks. She is a backup singer in her band the Dazzlings, rivaling the Rainbooms.

Development and design
Like those of her bandmates Adagio Dazzle and Aria Blaze, Sonata Dusk's fin-like wings are translucent and non-feathered.

In music terms, the word "sonata" refers to a composition for an instrumental soloist, often with a piano accompaniment.

Depiction in Rainbow Rocks
The Dazzlings, including Adagio Dazzle, Sonata Dusk, and Aria Blaze, appear in My Little Pony Equestria Girls: Rainbow Rocks as the main antagonists.

In the film, Sonata and the other Dazzlings are introduced in the human world. They are sirens from Equestria who were banished to the human world by Star Swirl the Bearded. They are first seen in a café causing tension between the patrons, and Sonata briefly argues with Aria Blaze. She and the Dazzlings later convince the students with their music to turn the friendly Musical Showcase into a Battle of the Bands.

Sonata and the Dazzlings use their siren's songs to control the students' opinion and advance through the competition bracket. Throughout the film, she is shown to be somewhat air-headed and carefree. She doesn't pick up on Adagio's sarcasm when she says she "loves" the human world, and she speaks candidly with Sunset Shimmer about her and her friends' true nature, nearly blowing their cover. In addition, she frequently argues with Aria Blaze over trivial matters. Despite this, she shows at least some level of cruelty, as she appears to take pleasure in belittling Sunset.

In the final battle against the Rainbooms, Sonata and the Dazzlings are eventually defeated and the gem pendants with which they controlled the students are destroyed. As a result, their inability to sing leads to them being chased off in disgrace.

Aside from flashbacks, Sonata's true form is never physically shown in the film, but she and her fellow band members gain pony-like ears, extended ponytails, and translucent fin-like wings. They also summon astral projections of their true siren forms from their pendants.

Personality
Throughout the film, Sonata Dusk is shown to be rather ditzy, excitable, and easily distracted, similar to Pinkie Pie. For example, before they sing their song in the cafeteria, Sonata is more focused on getting lunch since it is Taco Tuesday. Also, she and Pinkie are the only ones who actually seem to enjoy Snips and Snails' rap performance.

Nonetheless, Sonata can be just as cruel and devious as her bandmates, if at times unintentionally so, as evidenced in her interactions with Sunset Shimmer and Trixie.

Merchandise and promotional material
A doll of Sonata Dusk has been displayed, with packaging additionally showing her and Aria Blaze's pony versions, at the 2014 American International Toy Fair and on Hasbro's online listings of the product.

Hasbro's Equestria Girls website includes Sonata Dusk.

Hasbro.com Rainbow Rocks description
''Quirky and unpredictable, Sonata Dusk’s whimsical approach to everything adds a special kind of sparkle to The Dazzlings. Audiences are always enchanted by her magical voice, and her antics only turn up the volume.''

Quotes
"For realsies? Because I think this place is the worst."

- My Little Pony Equestria Girls: Rainbow Rocks

"We sing, like, all the time! It's how we get people to do what we want."

- My Little Pony Equestria Girls: Rainbow Rocks

"Wha-what did I say?"

- My Little Pony Equestria Girls: Rainbow Rocks

"But we can get lunch after though, right? It's Taco Tuesday!"

- My Little Pony Equestria Girls: Rainbow Rocks

"It's the fruit punch, isn't it? I knew I used too much grape juice!"

- My Little Pony Equestria Girls: Rainbow Rocks

"Too bad! So sad!"

- My Little Pony Equestria Girls: Rainbow Rocks

"She didn't shove them. She pulled a lever."

- My Little Pony Equestria Girls: Rainbow Rocks

"I think you're worser than the worst, Aria."

- My Little Pony Equestria Girls Rainbow Rocks - The Mane Event