I'm almost done with the base Galar Pokédex. I just have to obtain the Type: Null line now, they're going to be a pain to get since they're only available in the post-game as a gift Pokémon in the Battle Tower.
There is also a secret event nobody knows about. You have to play as a girl to trigger it.
Warning! It won't work If you don't have Boltund at your first team slot and five Alcremie.
First, you do camping at the wild area. You have to eat 88 currys in a row and leave the menu between each time.
If a battle occurs inbetween, you have to restart.
When you're done, you go to the steakhouse in circhester where you can find Dear Feeder looking for fat girls to caress.
When he spots you waddling through the door, he'll chase you with huge affection.
You can battle and catch him now. However, If you catch him while having moomoo cheese in your inventory, he'll get an autistic meltdown about cheese and it'll crash and corrupt the game. Your save file gets deleted and every time you try to start a new game you will see a shattered image of Elon Musk autistically staring at you.
So yeah it can turn your 60 bucks triple A game into an useless brick but it's worth it.
I highly recommend trying this at home, as dear feeder is very powerful and can use the incredible secret technique permaban, which can be unlocked at the fairy gym, but that's a story for another day.