Gundam Build Divers S02 E16 To the Heavenly Land

Riding in a balloon made by collecting the lanterns from the Space Crossing festival, Parviz and Freddie go to meet the sacred beast Cuadorn, which dwells in the floating temple known as Milaag Mountain. Buffeted by strong winds, the balloon continues its ascent, but ahead of it lies a huge thundercloud like nothing they've never seen before.