Which Pokémon games were the first main-series titles rendered in full 3D?

Pokémon X and Y were the first main-series Pokémon games rendered in full 3D.

Released worldwide for the Nintendo 3DS in 2013, Pokémon X and Y moved the core series from the primarily sprite-based presentation used by earlier handheld entries to polygonal 3D environments and character models. The games are set in the Kalos region, which is inspired by France, and they introduced the sixth generation of Pokémon.

The 3D presentation is different from earlier games that used limited effects, simulated depth, or 3D elements in selected locations. Pokémon X and Y applied the visual change throughout the main adventure, including exploration, battles, and character scenes. They also introduced Fairy-type Pokémon and Mega Evolution. Pokémon Sun and Moon continued the 3DS era, while Omega Ruby and Alpha Sapphire were 3D remakes released after X and Y. Therefore, those later titles do not take the franchise's first full-3D main-series position.