All sidequests should either have a WIP or a Completed checkmark. As for Blackjack, I suggest to look at the skills you have. If you want specific answers you can ask on the Spoiler/Guide post
Beat blackjack and yeh all side quests have one of those marks now except the shiny one, since am missing one of the 8 shinies? and I have no idea where it could be even after doing all the side stuff, I have went back and looked through areas as well
I had reports of the shiny being missing. But I checked and all shinies exist. So one in particular is hidden enough to be missed. I think I'll update a bit later the guide to show all locations for those who have problems finding it.
