Wandering Adventure Party

I think it must have been Xananthar’s for D&D 5e. I’d been playing for ages, but that was the first book I wanted a physical copy of. I have a copy of the Player’s Handbook as well now, and more recently, I bought the FFXIV TTRPG, as well as the Star Trek Adventures: Lower Decks splatbook. Everything else is digital or improvised