Melody and her band in silhouette to reference that you'll see them in full when the monster is Summoned. The card's info says:
The Rockin’ Beats
Special Summon 1 “My Little Pony Melody& the Rockin’ Beats” from your hand or deck.
2 years, 7 months ago
27 Jun 2016 04:04 CEST
Full Size: a93a00a6c8d44c028eeb615e47de54a6