The sixth edition of the famous Harold van der Heijden endgame study database (HHdbVI) is available now. The new edition not only has more than eight thousand extra studies, but also the solutions of thousands of studies were corrected or updated. It is by far the most comprehensive collection of endgame studies available.
The previous editions from 1991, 2000, 2005, 2010, and 2015 contained 23,358; 58,801; 67,691; 76,132; and 85,619 endgame studies, respectively. The new version has no less than 93,839 endgame studies. When you would undertake to play through all the studies at a rate of 3 minutes per study for 3 hours EVERY day, it would take you four years and four months to accomplish that task. That would be just in time for the next update!