The abandoned cistern puzzle is one of those easy-to-miss pieces of content in Baldur’s Gate 3, but anyone who’s following the Jaheira/Minsc storyline or has encountered the Stone Lord in the Counting House will find themselves in Baldur’s Gate’s damp and dank underbelly eventually. In order to progress both Jaheira’s companion quest and the quest to investigate the Stone Lord, you’ll need to follow Minsc’s trail down into the sewers after you confront him at the Counting House. Once here, you’ll find yourself faced with a few fights as well as a tricky puzzle.