«Princess Platinum». It's a really, really old ballad...

Song (and performance) by: Pony Band
https://goo.gl/JBCBDw

Directed by:
— Architect

Script by:
— OneStrangePerson

Animation by:
— Lost_Human
— DivineBrush

Arts by:
— DivineBrush
— Eriadu

Subtitles by:
— Anatoly136UA
— AlexFLS (English Translation)

Music (in credits) by:
— [BC]afGun
https://goo.gl/Alpnxf

Special thanks to:
— Longren
— WorstPony