The fifth edition of the famous Harold van der Heijden endgame study database (HHdbV) is available now. The new edition not only has more than nine thousand extra studies, but also the solutions of tens 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, and 2010 contained 23358, 58801, 67691, and 76132 endgame studies, respectively. The new version has no less than 85,619 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 cost you almost four years to accomplish that task!