Pokémon Sun and Moon - Ash & Lillie vs Lusamine animation by Masaaki Iwane

Also I'm sad this doesn't mean anything for the anime now.

Pokemon always starts out lighthearted and gets darker and more serious towards the end, XYZ was the same.

And Pokemon has never been able to explicitly state that a Pokemon died, that isn't new to SM. They weren't even allowed to show a kiss in XY.