Update: Caught Tornadus, I feel like my lung capacity has decreased by about 2%.
Yeah, no. I mean this as respectfully as I can say it: whoever on the development team designed those nightmarish encounters should not be allowed to come back. Those fights are not fun in the slightest, and I have more fun trying and failing to find a shiny Hisuian Zorua. Landorus was surprisingly easy compared to its brethren, but dear god, please do not let any other Pokémon game have encounters that are THAT bad. I know Enamorus is the last one, but I'm only going to full-catch the dex once for Arceus. After that I will reset and I will not be bothering to try a full completion SOLELY because of the Forces of Nature.