It's out it's a DMs Guild thing supporting Extralife.
Minsc and Boo's Journal of Villainy (5e) - Wizards of the Coast | D&D 5th Edition | Dungeon Masters Guild
Minsc and Boo's Journal of Villainy (5e) - All proceeds from this journal benefit Extra Life. Extra Life unites thousands of gamers around the world to play games
From the Journal of the Legendary Ranger and his Pet Hamster
A century has passed since the Bhaalspawn fought over the legacy of their father — Bhaal, the Lord of Murder. Two heroes witnessed the epic struggle firsthand — the ranger Minsc and his faithful companion, Boo.
Minsc and Boo were able to track down old friends and hated enemies and find out what they’ve been up to over the past century. They’ve compiled everything into this journal, edited by the traveler extraordinaire, Volo Geddarm.
Included in this journal are four cities, including Athkatla and Baldur’s Gate; ten group patrons led by some of Minsc and Boo’s old friends; a dozen new monsters; six arch villains and eleven dastardly henchmen.