Nightmare Remix (New game plus) Full Evs (Deadless, Set mode, No Items, No Bag): Sylveon's mother is the best
Before all this, there are some interesting things I can achieve before this big return with my good friend Cain. I got the Scolipede with Swords Dance as soon as I reached Route 7, and with a Technique Contract, it's officially a permanent member of the team.
Within this, it's important to clarify something about Sylveon:
Swift learns it at level 17. It's possible to get it by going back a level to level 16 thanks to candies, so there's no real consequence to this. Even if there were other problems with this Pokémon, I also have another Eevee with Calm Mind in my PC that I got before my trip to the GDC (I was looking for one with Toxic, but that's another story). Although, to save time, I ended up using Relearned Move.
But let's leave aside a few things about this battle, because things are getting interesting:
Our good friend starts with Starlight Terrain and then transforms into New World, which you have to be careful of since this Pokémon is treated like a Darkrai, as in one phase it has its more reliable and improved Dark Void. This isn't the only way it can put you to sleep, since it will always put you to sleep on turn 4 and apply the Nightmare effect. Because of this, I opted for a simple solution: using Saveguard on turns 2 and 3 to prevent them from falling asleep so quickly.
It's a bit complicated, but if you do everything right, that's where I needed the speed boost and the ability to withstand a Psyshock. With good Iron Defense and a significant investment in HP, it can handle it well, and then it's simply a matter of passing and using Calm Mind.
That's literally the plan, and it's not good to get overconfident because it will destroy you in one hit, even with Bold and all the buffs on its last shield.
I hope you like it. By the way, I apologize in advance; the post was uploaded without any prior notification. I don't know what happened to cause it to upload unexpectedly.