This is the finale of this series. Spike and Rarity, now ascended into gods, are in the midst of creating new planets to raise their ever-growing family. Spike does the “heavy lifting” of the process, meaning the creation of the planet core and mantle, the planet’s crust and mountain ranges, the oceans, etc. Dragon magic is primal and more closely attuned to the building blocks of reality, so this task is easier for him. Once he’s done, Rarity comes in and does the “finer details” such as the atmosphere and weather, the flora and ecosystems, and more.
Rarity can’t help but admire Spike as he works. He certainly does make for an impressive and powerful figure, and he only becomes more so with time. Perhaps Spike doesn’t realize he’s accidentally putting on a show for her, but then again, perhaps he does. It certainly wouldn’t be the first time they’d shown off to each other… like when Rarity had shown him a new maternity dress, oh so very long ago.
Variants (18 total, but actually 5, just mixed and combined):